Bruton&#39;s tyrosine kinase inhibitors

ABSTRACT

Bruton&#39;s tyrosine kinase (Btk) inhibitors have the following Formula (I):

This application is a continuation-in-part of PCT/US2018/023455, filed on Mar. 21, 2018, which claims the benefit of U.S. Provisional Application No. 62/474,686, filed on Mar. 22, 2017, which is incorporated by reference for all purposes as if fully set forth herein.

FIELD OF THE INVENTION

Described herein are Bruton's tyrosine kinase inhibitors, methods of making such inhibitors, and pharmaceutical compositions containing such inhibitors.

BACKGROUND OF THE INVENTION

Bruton's tyrosine kinase (Btk) plays an important role in signal transduction in B cells and is a factor that contributes to the survival, differentiation, proliferation, and activation of B cells. There is currently a need for methods of treating diseases in which B cells or mast cells participate. Btk is also known to participate in mast cell activation and in the physiological functions of platelets. Therefore, Btk inhibitors are effective for the treatment of diseases in which B cells or mast cells participate, for example, allergic diseases, autoimmune diseases, inflammatory diseases, thromboembolic diseases, and cancers.

SUMMARY OF THE INVENTION

The Btk inhibitors described herein have the following Formula (I):

In Formula (I), A, B, G, and D are each independently N or CR¹, with the proviso that only one or two of A, B, G, and D can be N; R¹ is hydrogen, —COOCH₃, —CH₂OH, —CH₂OCOCH₃, C₁₋₆alkyl, C₁₋₆cycloalkyl, C₁₋₄alkoxy, —O—C₁₋₄alkoxy, C₁₋₆alkyl substituted with one to five fluorines, C₁₋₄alkoxy substituted with one to five fluorines, C₁₋₄alkoxy substituted with OH, C₁₋₄alkoxy substituted with OCH₃, NH₂ or N(CH₃)₂, or

R² is

—X-E is one of the followings: (1) X is O, OCR^(a)R^(b), CR^(a)R^(b)O, S(O), S(O)₂, CR^(a)R^(b), NR^(c)(C═O), C═ONR^(c) or a bond; and E is a hydrogen, an aryl or a heteroaryl substituted with one to three R⁵ substituents; or a 3-7 membered saturated or partially unsaturated carbocyclic ring, an 8-10 membered bicyclic saturated, partially unsaturated or aryl ring, a 5-6 membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, a 4-7 membered saturated or partially unsaturated heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, a 7-10 membered bicyclic saturated or partially unsaturated heterocyclic ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an 8-10 membered bicyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; or (2) —X-E is hydrogen, halogen, —OR^(a), —O(CH₂)₁₋₄R^(a), —CN, —NO₂; R⁴ and R⁵ are each independently selected from the group consisting of hydrogen, halogen, hydroxy, cyano, OCF₃, OCF₂H, C₁₋₆ alkyl, optionally substituted with one to five fluorines, C₃₋₆ cycloalkyl, optionally substituted with one to five fluorines, C₁₋₄alkoxy, optionally substituted with one to five fluorines, C₁₋₄ alkylthio, optionally substituted with one to five fluorines, C₁₋₄ alkylsulfonyl, optionally substituted with one to five fluorines, carboxy, C₁₋₄ alkyloxycarbonyl, and C₁₋₄ alkylcarbonyl; R^(a) and R^(b) are each independently hydrogen, fluorine, or C₁₋₃ alkyl, optionally substituted with one to five fluorines; R^(c) is hydrogen or C₁₋₃ alkyl, optionally substituted with one to five fluorines; and R³ is a group having a double bond. Note in Formula (I), B can be N or C—H, and does not represent element boron; D can be N or C—H, and does not represent deuterium.

Further described is an isomer thereof, a tautomer thereof, a pharmaceutical acceptable solvate thereof, or a pharmaceutical acceptable prodrug thereof.

In one aspect, in Formula (I), E is selected from aryl, heteroaryl, carbocyclyl, heterocyclyl, any of which is optionally substituted with one to three R⁵ substituents.

In one aspect, in Formula (I), R³ is selected from the group consisting of:

Y is C(═O), OC(═O), NHC(═O), S═O, S(═O)₂, or NHS(═O)₂; and R⁶, R⁷, R⁸ are each independently hydrogen, halogen, CN, C₁₋₄ alkyl, C₁₋₆ alkoxyalkyl, C₁₋₈ alkylaminoalkyl, or C₁₋₄ alkylphenyl; or R⁷ and R⁸ taken together form a bond.

In one aspect, in Formula (I), R³ is selected from the group consisting of

Y is C(═O), OC(═O), NHC(═O), S═O, S(═O)₂, or NHS(═O)₂; R⁶, R, R⁸ are each independently hydrogen, halogen, CN, C₁₋₄ alkyl, C₁₋₆ alkoxyalkyl, C₁₋₈ alkylaminoalkyl, or C₁₋₄ alkylphenyl; and R⁷ and R⁸ are optionally taken together form a bond.

In one aspect, in Formula (I), R³ is selected from the group consisting of:

In one aspect, in Formula (I), A, G, and D are independently CR¹, and B is N.

In one aspect, in Formula (I), A is CR¹; G and D are CH; and B is N.

In one aspect, in Formula (I), G is CR¹; A and D are CH; and B is N.

In one aspect, in Formula (I), D is CR¹; A and G are CH; and B is N.

In one aspect, in Formula (I), R¹ is hydrogen, —COOCH₃, —CH₂OH, —CH₂OCOCH₃, —CH₃, —CH₂CH₃, —CH₂CH₂CH₃, —CH₂CH₂CH₂CH₃, —CH(CH₃)₂, —OCH₃, —OCH₂CH₃, —OCH₂CH₂CH₃, —OCH₂CH₂CH₂CH₃, —OCH(CH₃)₂, —CH₂F, —CF₃, —OCH₂CH₂OCH₃, —OCH₂CH₂N(CH₃)₂,

In one aspect, the compound of Formula (I) is selected from the group consisting of:

In another aspect, described herein is a pharmaceutical composition includes a therapeutically effective amount of the compound of Formula (I), and a pharmaceutically acceptable excipient.

In another aspect, described herein is a method for treating an autoimmune disease including administering to a subject in need thereof a composition containing a therapeutically effective amount of the compound of Formula (I).

In another aspect, in the method for treating an autoimmune disease, the composition is administered in combination with a therapeutic agent selected from the group consisting of: anticancer drugs, steroid drugs, methotrexates, leflunomides, anti-TNFa agents, calcineurin inhibitors, antihistaminic drugs, and a mixture thereof.

In another aspect, described herein is a pharmaceutical composition for preventing or treating cancers, tumors, inflammatory diseases, autoimmune diseases, or immunologically mediated disease including a therapeutically effective amount of the compound of Formula (I), and a pharmaceutically acceptable excipient.

In another aspect, described herein is a method for treating an autoimmune disease, cancers, tumors, inflammatory diseases, or immunologically mediated diseases including administering to a subject in need thereof a composition containing a therapeutically effective amount of the compound of Formula (I) and other therapeutic agents.

DETAILED DESCRIPTION OF THE INVENTION

The methods described herein include administering to a subject in need a composition containing a therapeutically effective amount of one or more Btk inhibitor compounds described herein.

Prodrugs means any compound which releases an active parent drug according to Formula I in vivo when such prodrug is administered to a mammalian subject. Prodrugs of a compound of Formula I are prepared by modifying functional groups present in the compound of Formula I in such a way that the modifications may be cleaved in vivo to release the parent compound. Prodrugs may be prepared by modifying functional groups present in the compounds in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to the parent compounds.

Tautomers mean compounds produced by the phenomenon wherein a proton of one atom of a molecule shifts to another atom. Tautomers also refer to one of two or more structural isomers that exist in equilibrium and are readily converted from one isomeric form to another. One of ordinary skill in the art would recognize that other tautomeric ring atom arrangements are possible. All such isomeric forms of these compounds are expressly included in the present disclosure.

Isomers mean compounds having identical molecular formulae but differ in the nature or sequence of bonding of their atoms or in the arrangement of their atoms in space. Isomers that differ in the arrangement of their atoms in space are termed stereoisomers. Stereoisomers that are not mirror images of one another are termed diastereomers, and those that are non-superimposable mirror images of each other are termed enantiomers. When a compound has an asymmetric center, for example, it is bonded to four different groups, a pair of enantiomers is possible. A chiral compound can exist as either individual enantiomer or as a mixture thereof. Unless otherwise indicated, the description is intended to include individual stereoisomers as well as mixtures.

Certain compounds of the present disclosure can exist in unsolvated forms as well as solvated forms, including hydrated forms. Solvates refer to a complex formed by combination of solvent molecules with the compound of Formula I. The solvent can be an organic compound, an inorganic compound, or a mixture thereof.

Pharmaceutically acceptable salts represent those salts which are, within the scope of medical judgement, suitable for use in contact for the tissues of humans and lower animals without undue toxicity, irritation, allergic response and the like, and are commensurate with a reasonable benefit/risk ratio. They may be obtained during the final isolation and purification of the compounds of the invention, or separately by reacting the free base function with a suitable mineral acid such as hydrochloric acid, phosphoric acid, or sulfuric acid, or with an organic acid such as for example ascorbic acid, citric acid, tartaric acid, lactic acid, maleic acid, malonic acid, fumaric acid, glycolic acid, succinic acid, propionic acid, acetic acid, methanesulfonic acid, and the like. The acid function can be reacted with an organic or a mineral base, like sodium hydroxide, potassium hydroxide or lithium hydroxide.

Therapeutically effective amount means an amount of compound or a composition of the present invention effective in inhibiting Bruton's tyrosine kinase and thus producing the desired therapeutic effect.

As used herein, the term alkyl refers to a monovalent straight or branched chain, saturated aliphatic hydrocarbon radical having a number of carbon atoms in the specified range. For example, C₁₋₆ alkyl refers to any of the hexyl alkyl and pentyl alkyl isomers as well as n-, iso-, sec- and t-butyl, n- and iso-propyl, ethyl and methyl. Alkyl also includes saturated aliphatic hydrocarbon radicals wherein one or more hydrogens are replaced with deuterium, for example, CD₃.

The term branched alkyl refers to an alkyl group as defined above except that straight chain alkyl groups in the specified range are excluded. As defined herein, branched alkyl includes alkyl groups in which the alkyl is attached to the rest of the compound via a secondary or tertiary carbon. For example, isopropyl is a branched alkyl group.

The term cycloalkyl refers to any monocyclic ring of an alkane having a number of carbon atoms in the specified range. For example, C₃₋₆cycloalkyl refers to cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl.

The term halogen refers to fluorine, chlorine, bromine and iodine (alternatively referred to as fluoro, chloro, bromo, and iodo).

The term haloalkyl refers to an alkyl group as defined above in which one or more of the hydrogen atoms have been replaced with a halogen (i.e., F, Cl, Br and/or I). For example, C₁₋₆ haloalkyl refers to a C₁ to C₆ linear or branched alkyl group as defined above with one or more halogen substituents. The term fluoroalkyl has an analogous meaning except that the halogen substituents are restricted to fluoro. Suitable fluoroalkyls include the series (CH₂)₀₋₄CF₃.

The term C(O) or CO refers to carbonyl. The terms S(O)₂ or SO₂ refers to sulfonyl. The term S(O) or SO refers to sulfinyl.

The term aryl refers to phenyl, naphthyl, tetrahydronaphthyl, idenyl, dihydroindenyl and the like. An aryl of particular interest is phenyl.

The term heteroaryl refers to (i) a 5- or 6-membered heteroaromatic ring containing from 1 to 4 heteroatoms independently selected from N, O and S, or (ii) is a heterobicyclic ring selected from quinolinyl, isoquinolinyl, and quinoxalinyl. Suitable 5- and 6-membered heteroaromatic rings include, for example, pyridyl (also referred to as pyridinyl), pyrrolyl, pyrazinyl, pyrimidinyl, pyridazinyl, triazinyl, thienyl, furanyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl, isooxazolyl, oxadiazolyl, oxatriazolyl, thiazolyl, isothiazolyl, and thiadiazolyl. A class of heteroaryls of interest consists of (i) 5- and 6-membered heteroaromatic rings containing from 1 to 3 heteroatoms independently selected from N, O and S, and (ii) heterobicyclic rings selected from quinolinyl, isoquinolinyl, and quinoxalinyl. Heteroaryls of particular interest are pyrrolyl, imidazolyl, pyridyl, pyrazinyl, quinolinyl (or quinolyl), isoquinolinyl (or isoquinolyl), and quinoxalinyl.

Examples of 4- to 7-membered, saturated heterocyclic rings within the scope of this invention include, for example, azetidinyl, piperidinyl, morpholinyl, thiomorpholinyl, thiazolidinyl, isothiazolidinyl, oxazolidinyl, isoxazolidinyl, pyrrolidinyl, imidazolidinyl, piperazinyl, tetrahydrofuranyl, tetrahydrothienyl, pyrazolidinyl, hexahydropyrimidinyl, thiazinanyl, thiazepanyl, azepanyl, diazepanyl, tetrahydropyranyl, tetrahydrothiopyranyl, and dioxanyl. Examples of 4- to 7-membered, unsaturated heterocyclic rings within the scope of this invention include mono-unsaturated heterocyclic rings corresponding to the saturated heterocyclic rings listed in the preceding sentence in which a single bond is replaced with a double bond (e.g., a carbon-carbon single bond is replaced with a carbon-carbon double bond).

It is understood that the specific rings listed above are not a limitation on the rings which can be used in the present invention. These rings are merely representative.

Synthetic methods for preparing the compounds of the present invention are illustrated in the following Schemes, Methods, and Examples. Starting materials are commercially available or may be prepared according to procedures known in the art or as described herein. The compounds of the invention are illustrated by means of the specific examples shown below. However, these specific examples are not to be construed as forming the only genus that is considered as the invention. These examples further illustrate details for the preparation of the compounds of the present invention. Those skilled in the art will readily appreciate that known variations in the conditions and processes can be used to prepare such compounds.

In Formula (I), A, B, G, R², and R³ are defined above in the Summary of the Invention section. The Btk inhibitor compounds of Formula (I) can be prepared by methods well known in the art of organic chemistry. The starting material used for the synthesis of these compounds can be either synthesized or obtained from commercial sources, such as, but not limited to, China chemical companies or Sigma-Aldrich Chemical Co. (St. Louis, Mo.) at China. The compounds described herein, and other related compounds having different substituents are optionally synthesized using techniques and materials, such as described, for example, in March, ADVANCED ORGANIC CHEMISTRY 4th Ed., (Wiley 1992); Carey and Sundberg, ADVANCED ORGANIC CHEMISTRY 4th Ed., Vols. A and B (Plenum 2000, 2001); Fieser and Fieser's Reagents for Organic Synthesis, Volumes 1-17 (John Wiley and Sons, 1991); Rodd's Chemistry of Carbon Compounds, Volumes 1-5 and Supplementals (Elsevier Science Publishers, 1989); Organic Reactions, Volumes 1-40 (John Wiley and Sons, 1991); and Larock's Comprehensive Organic Transformations (VCH Publishers Inc., 1989). Other methods for the synthesis of compounds described herein may be found in international Application Publication No. WO 2013/010868 A1, Liu, J. et al. ACS Medicinal Chemistry Letters 10 (2016) 198-203. The definitions of chemistry terms used in this application may be found in these reference (if not otherwise defined herein). As a guide the following synthetic methods may be utilized.

During the synthetic sequences, it may be necessary and/or desirable to protect sensitive or reactive groups on any of the molecules concerned. This is achieved by means of conventional protecting groups, such as those described in T.W. Greene and P.G.M. Wutts “Protective groups in Organic Synthesis” 3rd Edition, John Wiley and Sons, 1999. The protective groups are optionally removed at a convenient subsequent stage using methods well known in the art. The products of the reactions are optionally isolated and purified. If desired, using conventional techniques, but not limited to, filtration, distillation crystallization, chromatography and the like. Such materials are optionally characterized using conventional means, including physical constant and spectra data.

Compounds described herein may possess one or more sterocenters and each center may exist in the R or S configuration. The compounds presented herein include all diasterometic, enantiomeric, and epimeric forms as well as the appropriate mixtures thereof.

The Btk inhibitor compounds of Formula I can be, for example imidazo [1,5-a] pyrazine derivatives. Specifically, the Btk inhibitor compounds of Formula I can be, for example, compounds G, wherein R₁-R₂ have the previously defined meanings. A non-limiting example of a synthetic approach towards the preparation of compounds G can be prepared by the general synthetic route shown in Scheme I and Scheme II.

Referring to Scheme I, different amine (B) can be obtained by hydrogenation of aromatic nitrile, and then can be reacted with an appropriately amine protected amino acid in a solvent such as DMF, THF or DCM in the presence of a base such as TEA, DIPEA, DMAP and with different coupling reagents such as PyBOP, TBTU, EDCI or HATU to form intermediate C. Cyclization C can be used the condensation reagents like PCl₃ under heating conditions to provide the key intermediate D, subsequent bromination can be achieved using bromine or N-bromosussinimide in a solvent like DCM or DMF at appropriate temperature to obtain compounds of E, then react with appropriate boronic acid or pinacol ester in which FG is a functional group (e.g. ester, protected anilines, protected phenols, bromide), which then are derivatived by metal catalyst coupling reaction using appropriately substituted phenylboronic acid (corresponding boronic esters may also be used) directly affords the desired compounds G. In a typical procedure, a mixture of intermediates F, a copper catalyst (e.g. Cu(OAc)₂), base (e.g. TEA, DIPEA or the like) and an aryl boronic acid or aryl boronic ester in a suitable solvent such as DCM, or toluene to form compounds G (FG is converted to groups defined for XAr). Finally, deprotected Cbz with the compounds H give the unprotected amine which react with appropriate warheads R₂ with previously defined meanings, provided compounds of compound H.

Referring to Scheme II, compounds P can be obtained from another substrate, and the chemistry is similar with Scheme I, Methyl derivatives L can be prepared using trimethylboroxin in the presence of a suitable palladium catalyst system and solvent, then key intermediates M was obtained by regioselective bromination or iodation with Br₂/I₂ or NBS/NIS, which then are derivatived by metal catalyst coupling reaction using appropriately substituted phenylboronic acid (corresponding boronic esters may also be used) affords a key intermediate N or directly affords the desired compounds O. The transformation from O to P is synthesized in a similar manner as before showed at Scheme I.

Alternatively, compound G (or O) can be obtained from compounds F (or N), in which FG is a functional group (e.g. ester, protected anilines, protected phenols, bromide) that can be easily converted to groups defined for XAr. Non-limiting examples of suitable functional groups in compounds F are a benzyl ether, dibenzyl anime, or methyl ester, which can be treated with base or Pd/C/H₂ to form the key intermediates F-1a, F-2a, F-3a (or N-1a, N-2a, N-3a), then form corresponding compounds G-1, G-2, G-3, G-4 (or O-1, O-2, O-3, O-4) at Scheme III.

The deprotection reactions for the protective groups of compound G in Scheme IV are known and can be run by the methods described below. Examples here are (a) deprotection reaction under acid or basic conditions for Boc or Fmoc protecting group and (b) deprotection reactions based on hydrogenolysis for benzyl or Cbz protecting group. After deprotection with these conditions, coupling with, but not limited to, an acid chloride, such as, but not limited to, aryloyl chloride, completes the synthesis to provide compound G-b.

The present invention also embraces isotopically-labelled compounds of the present invention which are identical to those recited herein, but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or number usually found in nature. Examples of isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, fluorine and chlorine, such as ²H, ³H, ¹³C, ¹⁴C, ¹⁵N, ¹⁷O, ¹⁸O, ³¹P, ³²P, ³⁵S, ¹⁸F, and ³⁶Cl respectively.

Certain isotopically-labelled compounds of Formula I (e.g. those labeled with ³H and ¹⁴C) are useful in compound and/or substrate tissue distribution assays. Tritiated and carbon-14 isotopes are particularly preferred for their ease of preparation and detectability. Further, substitution with heavier isotopes such as deuterium may afford certain therapeutic advantages resulting from greater metabolic stability (e.g., increased in vivo half-life or reduced dosage requirements) and hence may be preferred in some circumstances. Isotopically labelled compounds of Formula I can generally be prepared by following procedures analogous to those disclosed in the schemes and/or in the examples herein below, by substituting and appropriate isotopically labeled reagent for a non-isotopically labeled reagent.

General experimental conditions: Preparative thin layer chromatography (PTLC) was performed on 20×20 cm plates (500 micron thick silica gel). Silica gel chromatography was performed on a Biotage Horizon flash chromatography system. ¹H NMR spectra were recorded on a Bruker Ascend™ 400 spectrometer at 400 MHz at 298° K, and the chemical shifts are given in parts per million (ppm) referenced to the residual proton signal of the deuterated solvents: CHCl₃ at δ=7.26 ppm and CH₃OH or CH₃OD at δ=3.30 ppm. LCMS spectra were taken on an Agilent Technologies 1260 Infinity or 6120 Quadrupole spectrometer. The mobile phase for the LC was acetontrile (A) and water (B) with 0.01% formic acid, and the eluent gradient was from 5-95% A in 6.0 min, 60-95% A in 5.0 min, 80-100% A in 5.0 min and 85-100% A in 10 min using a SBC18 50 mm×4.6 mm×2.7 m capillary column. Mass spectra (MS) were measured by electrospray ion-mass spectroscopy (ESI). All temperatures are in degrees Celsius unless otherwise noted.

Analytical HPLC mass spectrometry conditions:

LC1: Column: SB-C18 50 mm×4.6 mm×2.7 m; Temperature: 50 OC; Eluent: 5:95 v/v acetonitrile/water+0.01% formic acid in 6 min; Flow Rate: 1.5 mL/min, Injection 5 μL; Detection: PDA, 200-600 nm; MS: mass range 150-750 amu; positive ion electrospray ionization.

LC2: Column: SB-C18 50 mm×4.6 mm×2.7 m; Temperature: 50 OC; Eluent: 5:95 to 95:5 v/v acetonitrile/water+0.05% TFA over 3.00 min; Flow Rate: 1.5 mL/min, Injection 5 μL; Detection: PDA, 200-600 nm; MS: mass range 150-750 amu; positive ion electrospray ionization.

LC3: Column: SB-C18 50 mm×4.6 mm×2.7 μm; Temperature: 50° C.; Eluent: 10:90 to 98:2 v/v acetonitrile/water+0.05% TFA over 3.75 min; Flow Rate: 1.0 mL/min, Injection 10 μL; Detection: PDA, 200-600 nm; MS: mass range 150-750 amu; positive ion electrospray ionization.

List of Abbreviations: AcOH=acetic acid; Alk=alkyl; Ar=aryl; Boc=tert-butyloxycarbonyl; bs=broad singlet; CH₂Cl₂=dichloromethane; d=doublet; dd=doublet of doublets; DBU=1,8-diazabicyclo-[5.4.0]undec-7-ene; DCM=dichloromethane; DEAD=diethyl azodicarboxylate; DMF=N,N-dimethylformamide; DMSO=dimethyl sulfoxide; EA=ethyl acetate; ESI=electrospray ionization; Et=ethyl; EtOAc=ethyl acetate; EtOH=ethyl alcohol; h=hours; HOAc=acetic acid; LiOH=lithium hydroxide; m=multiplet; Me=methyl; MeCN=acetonitrile; MeOH=methyl alcohol; MgSO₄=magnesium sulfate; min=minutes; MS=mass spectroscopy; NaCl=sodium chloride; NaOH=sodium hydroxide; Na₂SO₄=sodium sulfate; NMR=nuclear magnetic resonance spectroscopy; PE=petroleum ether; PG=protecting group; Ph=phenyl; rt=room temperature; s=singlet; t=triplet; TFA=trifluoroacetic acid; THF=tetrahydrofuran; Ts=p-toluenesulfonyl (tosyl).

The compounds of the present invention can be prepared following general methods detailed below. In certain embodiments, provided herein are methods of making the tyrosine kinase inhibitor compounds described herein. In certain embodiments, compounds described herein are synthesized using the following synthetic schemes. In other embodiments, compounds are synthesized using methodologies analogous to those described below by the use of appropriate alterative starting materials. All key intermediates were prepared according to the following methods.

Example 1 (R)-1-(3-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)prop-2-en-1-one (7)

Step 1: Pyrazin-2-ylmethanamine (1)

Pyrazine-2-carbonitrile (19 g, 180 mmol) was dissolved in 1,4-dioxane (280 mL), and then Raney nickel (1.9 g) was added. The reaction mixture was reacted in hydrogen atmosphere at 60° C. for 48 hours. The mixture was filtered through Celite and the filtrate was concentrated under reduced pressure to obtain the title compound (1) (19 g, 98.9%) as a brown oil.

¹H NMR (400 MHz, DMSO-d₆): δ 871 (s, 1H), 8.54-8.53 (m, 2H), 8.48 (d, J=2.4 Hz, 1H), 3.86 (s, 2H), 1.97 (br, 2H).

Step 2: (R)-Benzyl 3-((pyrazin-2-ylmethyl)carbamoyl)piperidine-1-carboxylate (2)

To a solution of pyrazin-2-ylmethanamine (1, 5.0 g, 45.8 mmol), (R)-1-((benzyloxy)carbonyl)piperidine-3-carboxylic acid (12.6 g, 48.18 mmol) and HATU (20.8 g, 54.96 mmol) in dichloromethane (334 mL) was added TEA (25.4 mL, 183.2 mmol). The reaction mixture was stirred at 0° C. for 1 h and another 3 h at room temperature. The mixture was washed subsequently with 0.1 M HCl-solution, 5% NaHCO₃, water and brine. The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. Purification by flash column chromatography on silica gel (D/M=100:1-25:1) gave 2 (14.5 g, 89.5%).

¹H NMR (400 MHz, CDCl₃): δ 8.58 (s, 1H), 8.49 (s, 1H), 7.36-7.28 (m, 5H), 5.17-5.12 (m, 2H), 4.60 (s, 1H), 4.01-3.93 (m, 2H), 3.26-3.21 (m, 2H), 2.41-2.39 (m, 1H), 1.95-1.79 (m, 4H).

Step 3: (R)-Benzyl-3-(imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (3)

A mixture of (R)-benzyl 3-((pyrazin-2-ylmethyl)carbamoyl)piperidine-1-carboxylate (2, 3.0 g, 8.47 mmol) and POCl₃ (4.2 mL) in benzene (15 mL) was refluxed for 2 h. The reaction was quenched by the addition of the water, and the mixture was made basic with sat. NaHCO₃. It was extracted with (DCM, 20 mL×3). The combined organic layers were washed with brine, dried over Na₂SO₄ and evaporated in vacuo. Purification by flash column chromatography on silica gel (D/M=100:1-50:1) gave 3 (0.4 g, 12.5%).

¹H NMR (400 MHz, CDCl₃): δ 8.84 (s, 1H), 7.65 (s, 1H), 7.30-7.26 (m, 1H), 7.25-7.19 (m, 6H), 5.22 (s, 2H), 5.14-5.08 (m, 2H), 4.36-4.21 (m, 2H), 3.05-2.86 (m, 3H), 2.18-2.10 (m, 2H), 1.96-1.90 (m, 1H), 1.83-1.80 (m, 1H). LCMS: m/z=337 [M+H]⁺

Step 4: (R)-benzyl 3-(1-bromoimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate(4)

To a solution of (R)-benzyl 3-(imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (3, 0.35 g, 1.04 mmol) in THF (6 mL) at 0° C., was added NBS (0.18 g, 1.04 mmol). The solution was stirred room temperature for 1 h. The reaction was quenched by the addition of water, and the mixture was made basic with sat. NaHCO₃. The mixture was extracted with (DCM, 20 mL×3). The combined organic layers were washed with brine, dried over Na₂SO₄ and evaporated in vacuo. Purification by flash column chromatography on silica gel (D/M=100:1-50:1) gave 4 (0.28 g, 63.8%).

¹H NMR (400 MHz, CDCl₃): δ 8.76 (s, 1H), 7.66-7.49 (m, 1H), 7.41-7.39 (m, 6H), 7.25-7.19 (m, 6H), 5.14-5.06 (m, 2H), 4.32-4.19 (m, 2H), 3.04-2.84 (m, 3H), 2.18-2.10 (m, 2H), 1.96-1.90 (m, 1H), 1.83-1.80 (m, 1H). LCMS: m/z=416, 417 [M+H]⁺.

Step 5: (R)-Benzyl 3-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (5)

A solution of (R)-benzyl 3-(1-bromoimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (4, 0.20 g, 0.48 mmol), (4-(2-fluoro-3-methoxyphenoxy)phenyl)boronic acid (0.16 g, 0.62 mmol), Pd(dppf)Cl₂ (35 mg, 0.048 mmol), and K₂CO₃ (0.13 g, 0.96 mmol) in dioxene/H₂O(=5/1, 6 mL) was heated to reflux for 5 h under nitrogen atmosphere. Water (10 mL) was added, and the mixture was extracted with EA (20 mL×3). The combined organic layers were washed with brine, dried over Na₂SO₄ and evaporated in vacuo. Purification by flash column chromatography on silica gel (D/M=50:1) gave 5 (0.21 g, 80.7%).

¹H NMR (400 MHz, CDCl₃): δ 9.07 (s, 1H), 7.76 (d, J=8 Hz, 2H), 7.41-7.39 (m, 6H), 7.03 (d, J=8 Hz, 2H), 6.96-6.92 (m, 1H), 6.74-6.70 (m, 1H), 6.63-6.60 (m, 1H), 5.14-5.06 (m, 2H), 4.32-4.19 (m, 2H), 3.04-2.84 (m, 3H), 2.18-2.10 (m, 2H), 1.96-1.90 (m, 1H), 1.83-1.80 (m, 1H). LCMS: m/z=553.1 [M+H]⁺.

Step 6: (R)-1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)-3-(piperidin-3-yl)imidazo[1,5-a]pyrazine (6)

A solution of (R)-benzyl 3-(1-(4-(2-fluoro-3-methoxyphenoxy)-phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (5, 0.2 g, 0.36 mmol) in 33% HBr (in AcOH, 5 mL) was stirred at room temperature for 3 h. Water was added, and the mixture was extracted with EA (20 mL).

The aqueous phase was neutralized using NH₃.H₂O, and then the mixture was extracted with DCM (10 mL×3). The combined organic layers were washed with brine, dried over Na₂SO₄ and evaporated in vacuo gave 6 (0.15 g, 99.3%). LCMS: m/z=419 [M+H]⁺.

Step 7: (R)-1-(3-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)prop-2-en-1-one (7)

A solution of acryloyl chloride (3.5 mg, 0.036 mmol) in DCM (1 mL) was added to a stirred solution of (R)-1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)-3-(piperidin-3-yl)imidazo[1,5-a]pyrazine (6, 15 mg, 0.036 mmol), and TEA (0.1 mL) in DCM (5 mL) at 0° C. The reaction mixture was stirred for 1 h, and poured into brine. It was extracted with DCM. The organic layer was dried over Na₂SO₄ and evaporated in vacuo. Purification by TLC (D/M=20:1) gave 7 (7 mg, 41.4% 2 steps).

¹H NMR (400 MHz, CDCl₃): δ 9.16 (s, 1H), 7.85 (d, J=8 Hz, 2H), 7.54 (s, 1H), 7.11 (d, J=8 Hz, 2H), 7.03-7.01 (m, 1H), 6.75-6.72 (m, 1H), 6.71-6.68 (m, 2H), 6.39-6.28 (m, 1H), 5.71-5.69 (m, 1H), 4.91-4.88 (m, 1H), 4.70-4.68 (m, 0.5H), 4.22-4.20 (m, 0.5H), 4.12-4.09 (m, 1H), 3.93 (s, 3H), 3.28-3.18 (m, 2H), 2.97-2.91 (m, 1H), 2.34-2.28 (m, 2H), 2.02-1.93 (m, 2H). LCMS: m/z=553.1 [M+H]⁺.

Example 2 (R,E)-2-(3-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carbonyl)-4,4-dimethylpent-2-enenitrile (9)

Step 1: (R)-3-(3-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)-3-oxopropanenitrile (8)

To a solution of (R)-1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)-3-(piperidin-3-yl)imidazo[1,5-a]pyrazine (6, 50 mg, 0.11 mmol), 2-cyanoacetic acid (14.5 mg, 0.17 mmol) and HATU (68 mg, 0.17 mmol) in dichloromethane (4 mL) was added TEA (44.4 mg, 0.44 mmol) and the reaction mixture was stirred at room temperature for 3 h. The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. Purification by TLC (D/M=20:1) gave 8 (20 mg, 37.7%). LCMS: m/z=486 [M+H]⁺.

Step 2: (R,E)-2-(3-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carbonyl)-4,4-dimethylpent-2-enenitrile (9)

A solution of (R)-3-(3-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)-3-oxopropanenitrile (6, 10 mg, 0.02 mmol) and pivalaldehyde (0.17 mL) in acetic acid (2 mL) was stirred at 80° C. for 6 h. Water was added, and the mixture was extracted with EA (10 mL×3). The combined organic layers were washed with brine, dried over Na₂SO₄ and evaporated in vacuo. Purification by TLC (D/M=20:1) gave 9 (2.5 mg, 22.7%). LCMS: m/z=554 [M+H]⁺.

Example 3 (R)-2-(3-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)-2-oxoacetamide (11)

Step 1: (R)-Methyl 2-(3-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)-2-oxoacetate (1)

To the solution of (S)-1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)-3-(piperidin-3-yl)imidazo[1,5-a]pyrazine (crude, 0.12 mmol 1.0 eq) in DCM (5.0 mL) was added triethylamine (24 mg, 0.024 mmol). Then methyl 2-chloro-2-oxoacetate (18 mg, 0.12 mmol, 1.2 eq) was added dropwise under ice water bath and the mixture was stirred for 1 h. The mixture was quenched with MeOH and the mixture was evaporated to dryness to give the crude product. LCMS: m/z=505 [M+H]⁺.

Step 2: (R)-2-(3-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)-2-oxoacetamide (2)

Compound 1 (10 mg, 0.02 mmol) was dissolved in NH₃/MeOH (7 M, 5.0 mL) and stirred at room temperature for 2 h. The solvent was removed and the residue was purified by prep-TLC to afford the titled product (8.3 mg, 80%).

¹H NMR (400 MHz, CDCl₃): δ 9.08 (s, 1H), 7.98-7.97 (m, 1H), 7.77-7.75 (m, 2H), 7.51-7.49 (m, 1H), 7.06-6.93 (m, 4H), 6.74-6.60 (m, 2H), 5.84 (s, 1H), 4.77-4.75 (m, 1H), 4.45-4.42 (m, 1H), 3.85 (s, 3H), 3.36-3.27 (m, 2H), 2.88-2.79 (m, 1H), 2.22-2.16 (m, 2H), 1.96-1.92 (m, 1H), 1.69-1.60 (m, 1H). LCMS: m/z=490 [M+H]⁺.

Example 4 (S)-1-(2-(1-(6-Phenoxypyridin-3-yl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (4)

Step 1: 2-Phenoxy-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (1)

The suspension of SM (1.4 g, 5.6 mmol,), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (1.7 g, 6.7 mmol), PdCl₂(dppf) (245 mg, 0.3 mmol), and potassium acetate (1.6 g, 16.8 mmol) in DMF (20 mL) was stirred at 80° C. for 20 h. The mixture was then cooled to room temperature, diluted with water and extracted with EA. The combined organic layers were washed with water, brine, and dried over anhydrous sodium sulfate. The solvent was removed in vacuum and the residue was purified by silica gel column chromatography (PE) to afford the desired product (414 mg, yield 25%).

Step 2: (S)-benzyl-2-(1-(5-phenoxypyridin-2-yl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (2)

The mixture of 1 (111 mg, 0.38 mmol), (S)-benzyl 2-(1-bromoimidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (100 mg, 0.25 mmol), PdCl₂(dppf) (15 mg), and potassium carbonate (69 mg, 0.50 mmol) in DMF (10 mL) was stirred at 80° C. for 21 h. The mixture was then cooled to room temperature, diluted water and extracted with EA. The combined organic layers were washed with water, brine, and dried over anhydrous sodium sulfate. The solvent was removed in vacuum and the residue was purified by silica gel column chromatography (PE/EA=10:1-6:1) to give the desired product (74 mg, yield 60%).

¹H NMR (400 MHz, CDCl₃): δ 9.05 (d, J=41.2 Hz, 1H), 8.69 (d, J=21.6 Hz, 1H), 8.28-8.17 (m, 1H), 7.66 (dd, J=12.0, 7.6 Hz, 1H), 7.57-7.53 (m, 1H), 7.50-7.38 (m, 4H), 7.25-7.15 (m, 4H), 7.15-7.09 (m, 1H), 7.05-7.00 (m, 1H), 6.88 (d, J=6.4 Hz, 1H), 5.35-5.20 (s, 1H), 5.18-4.96 (m, 2H), 3.83-3.59 (m, 2H), 2.68-2.4 (m, 2H), 2.15-2.00 (m, 2H). LCMS: m/z=492 [M+H]⁺.

Step 3: (S)-1-(4-(Pyridin-3-yloxy)phenyl)-3-(pyrrolidin-2-yl)imidazo[1,5-a]pyrazine (3)

A mixture of 2 (68 mg, 0.14 mmol, 1.0 eq) in DCM (2.0 mL) and 33% HBr/acetic acid (2.0 mL) was stirred at room temperature (20° C.) for 0.5 h. It was then diluted with water, and extracted with DCM. The pH of aqueous phase was adjusted to 8 with ammonium hydroxide. The mixture was extracted with DCM. The combined organic layers were washed with water, brine, and dried over Na₂SO₄. The solution was filtered and the solvent was removed by rotary evaporation to give crude 3 (36 mg). LCMS: m/z=358 [M+H]⁺.

Step 4: (S)-1-(2-(1-(4-(Pyridin-3-yloxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (4)

To a solution of 3 (18 mg, 0.05 mmol) and TEA (0.05 mL) in DCM (20 mL), was added acryloyl chloride (5.0 mg, 0.05 mmol). The mixture was stirred at 10° C. for 10 min, and then the mixture solution was quenched with methanol (2.0 mL). The residue was purified with prep-TLC to give 4 (8.3 mg, 40%).

¹H NMR (400 MHz, CDCl₃): δ 9.09 (s, 1H), 8.71 (d, J=2.0 Hz, 1H), 8.35 (d, J=4.0 Hz, 1H), 8.20 (dd, J=8.4, 2.4 Hz, 1H), 7.59 (d, J=4.8 Hz, 1H), 7.42 (t, J=8.0 Hz, 2H), 7.24-7.15 (m, 3H), 7.02 (d, J=8.4 Hz, 1H), 6.45 (dd, J=16.4, 10.0 Hz, 1H), 6.32 (dd, J=16.8, 2.0 Hz, 1H), 5.68 (dd, J=10.0, 1.6 Hz, 1H), 5.53 (dd, J=8.0, 3.2 Hz, 1H), 3.95-3.84 (m, 1H), 3.75 (t, J=8.5 Hz, 1H), 2.88-2.73 (m, 1H), 2.61-2.44 (m, 1H), 2.42-2.24 (m, 1H), 2.19 (dd, J=7.2, 4.8 Hz, 1H). LCMS: m/z=412 [M+H]⁺.

Example 5 (S)-1-(2-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)-8-methylimidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)but-2-yn-1-one (5)

Step 1: Benzyl (S)-2-(8-methylimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (2)

A mixture of 1 (220 mg, 0.59 mmol, 1.0 eq), TMB (148 mg, 1.19 mmol, 2 eq), Pd(PPh₃)₄ (68 mg, 0.059 mmol, 0.1 eq), and potassium carbonate (164 mg, 1.19 mmol, 2.0 eq) in DMF (5 mL) was stirred at 90° C. overnight. Water was added and the mixture was extracted with EA. The combined organic layers were washed with water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=200:1-50:1) to give the desired product 2 (145 mg, yield=70%). LCMS: m/z=351 [M+H]⁺.

Step 2: Benzyl (S)-2-(1-bromo-8-methylimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (3)

To a solution of 3 (145 mg, 0.41 mmol, 1.0 eq) in THF (2.5 mL) at 0° C., was added NBS (74 mg, 0.41 mmol, 1 eq). The mixture was stirred at 25° C. for 2 h. The mixture was diluted with water and the mixture was extracted with EA. The combined organic layers were washed with sodium bicarbonate, water and brine. The organic phase was dried over Na₂SO₄, and filtered. The solvent was removed by rotary evaporation. The residue was purified with silica gel column chromatography (DCM/MeOH=100:1-50:1) to give 3 (110 mg, yield 63%).

¹H NMR (400 MHz, CDCl₃): δ 7.84 (s, 1H), 7.36 (s, 5H), 5.76 (s, 1H), 5.19 (s, 2H), 4.12 (dd, J=13.4, 6.6 Hz, 1H), 3.99 (d, J=12.7 Hz, 1H), 2.89 (s, 3H), 2.73 (t, J=12.9 Hz, 1H), 2.46 (d, J=12.5 Hz, 1H), 2.35 (d, J=12.9 Hz, 1H), 2.05 (s, 1H), 1.97 (d, J=12.9 Hz, 1H), 1.79 (d, J=12.7 Hz, 1H), 1.71 (d, J=12.6 Hz, 1H), 1.54 (d, J=12.7 Hz, 1H). LCMS: m/z=429 [M+H]⁺.

Step 3: Benzyl (S)-2-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)-8-methylimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (4)

A mixture of 3 (110 mg, 0.26 mmol, 1.0 eq), (4-(2-fluoro-3-methoxyphenoxy)phenyl)boronic acid (101 mg, 0.39 mmol, 1.5 eq), PdCl₂(dppf) (19 mg, 0.026 mmol, 0.1 eq), and potassium carbonate (72 mg, 0.52 mmol, 2.0 eq) in dioxane (10.0 mL) and water (2.0 mL) was heated to reflux overnight. The mixture was allowed to cool to room temperature. Water was added and the mixture was extracted with EA. The combined organic layers were washed with water and brine. The organic phase was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=100:1) to give the desired product 4 (105 mg, yield 71.4%).

¹H NMR (400 MHz, CDCl₃): δ 7.83 (s, 1H), 7.51 (d, J=8.1 Hz, 2H), 7.37 (s, 5H), 7.05 (t, J=11.0 Hz, 3H), 6.81 (t, J=7.5 Hz, 1H), 6.72 (t, J=7.3 Hz, 1H), 5.85 (s, 1H), 5.22 (s, 2H), 4.12 (q, J=7.0 Hz, 3H), 4.01 (d, J=12.5 Hz, 1H), 3.93 (s, 3H), 2.80 (t, J=12.5 Hz, 1H), 2.66-2.35 (m, 5H), 2.01 (d, J=27.9 Hz, 5H), 1.79 (d, J=12.5 Hz, 2H), 1.70 (d, J=12.4 Hz, 1H), 1.56 (d, J=12.2 Hz, 1H). LCMS: m/z=567 [M+H]⁺.

Step 4: (S)-1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)-8-methyl-3-(piperidin-2-yl)imidazo[1,5-a]pyrazine (5)

A solution of 4 (105 mg, 0.19 mmol, 1.0 eq) in HBr/acetic acid (2.0 mL) was stirred at room temperature (22° C.) for 2 h. The solution was diluted with water, and the pH was adjusted to 7 with 2.0 M sodium hydroxide. The mixture was extracted with DCM, and the combined organic layers were washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give crude 5 (82 mg, yield 100%). LCMS: m/z=433 [M+H]⁺.

Step 5: (S)-1-(2-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)-8-methylimidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)but-2-yn-1-one (6)

To a solution of 5 (25 mg, 0.06 mmol, 1.0 eq) and TEA (9 mg, 0.09 mmol, 1.5 eq) in DCM (2.0 mL), were added but-2-ynoic acid (5 mg, 0.06 mmol, 1.0 eq) and HATU (27 mg, 0.07 mmol, 1.2 eq). The mixture was stirred at room temperature (25° C.) for 1 h, and then the mixture solution was diluted with water. The mixture was extracted with DCM. The organic layer was washed with water and brine. It was dried over Na₂SO₄, filtered and concentrated. The residue was purified with prep-TLC to give 6 (5 mg, yield 16.7%).

¹H NMR (400 MHz, CDCl₃): δ 7.94 (s, 1H), 7.49 (t, J=22.0 Hz, 3H), 7.06 (t, J=11.5 Hz, 4H), 6.81 (t, J=7.3 Hz, 1H), 6.73 (t, J=7.1 Hz, 1H), 6.24 (d, J=3.9 Hz, 1H), 4.21 (d, J=11.1 Hz, 1H), 3.94 (s, 3H), 3.02 (t, J=13.1 Hz, 1H), 2.68 (dd, J=30.6, 12.2 Hz, 2H), 2.02 (s, 3H), 1.96 (d, J=13.8 Hz, 1H), 1.83 (d, J=11.0 Hz, 2H), 1.72-1.54 (m, 3H). LCMS: m/z=499 [M+H]⁺.

Example 6 (S)-1-(2-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)prop-2-en-1-one (6)

Step 1: (S)-Benzyl-2-(((3-chloropyrazin-2-yl)methyl)carbamoyl)piperidine-1-carboxylate(1)

To a mixture of (3-chloropyrazin-2-yl)methanamine hydrochloride (3.9 g, 21.8 mmol, 1 eq) and (S)-1-((benzyloxy)carbonyl)piperidine-2-carboxylic acid (5.73 g, 21.8 mmol, 1.0 eq) in DCM (50 mL), was added TEA (12.1 mL, 87.2 mmol, 4.0 eq). The reaction mixture was cooled to 0° C. After 10 min, HATU (9.94 g, 26.2 mmol, 1.2 eq) was added, and the reaction mixture was stirred at 0° C. for 1 h and then at room temperature overnight. The mixture was washed subsequently with 0.1 M HCl-solution, 5% NaHCO₃, water and brine. It was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=200:1-50:1) to afford the desired product 1 (7.13 g, yield 84.4%). LCMS: m/z=389 [M+H]⁺.

Step 2: (S)-Benzyl-2-(8-chloroimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (2)

To a solution of compound 1 (1.0 g, 2.58 mmol, 1.0 eq) in DCM (6 mL), was added 2-fluoropyridine (276 mg, 2.84 mmol, 1.1 eq), followed by addition of Tf₂O (874 mg, 3.1 mmol) dropwise. The reaction mixture was stirred at 35° C. overnight. The reaction mixture was poured to H₂O, and the mixture was extracted with EA. The combined organic layers were washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=100:1-50:1) to give the desired product 2 (556 mg, yield 59%).

¹H NMR (400 MHz, CDCl₃): δ 7.93 (s, 1H), 7.79 (s, 1H), 7.36 (s, 5H), 7.19 (s, 1H), 5.82 (s, 1H), 5.19 (s, 2H), 4.01 (d, J=13.1 Hz, 1H), 2.70 (t, J=12.8 Hz, 1H), 2.42 (dd, J=30.5, 13.2 Hz, 2H), 2.01 (dd, J=23.4, 9.9 Hz, 1H), 1.83 (d, J=13.1 Hz, 1H), 1.76-1.44 (m, 3H). LCMS: m/z=371 [M+H]⁺.

Step 3: (S)-Benzyl-2-(imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (3)

To a mixture of compound 2 (129 mg, 0.25 mmol, 1.0 eq), triphenylphosphine (18 mg, 0.07 mmol, 0.2 eq), Pd(OAc)₂ (8 mg, 0.035 mmol, 0.1 eq), and potassium carbonate (72 mg, 0.52 mmol, 2.0 eq) was added n-butyl alcohol (5 mL). The reaction mixture was stirred under reflux for 1 h, and then it was allowed to cool to room temperature. The mixture was filtered and concentrated. Water was added and the mixture was extracted with EA. The organic layer was washed with water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=200:1-50:1) to give product 3 (87 mg, yield=75%).

¹H NMR (400 MHz, CDCl₃): δ 8.93 (s, 1H), 7.97 (s, 1H), 7.75 (s, 1H), 7.37 (s, 5H), 5.85 (s, 1H), 5.20 (s, 2H), 4.01 (d, J=13.0 Hz, 1H), 2.70 (t, J=12.3 Hz, 1H), 2.44 (dd, J=33.6, 13.3 Hz, 2H), 1.98 (d, J=13.0 Hz, 1H), 1.83 (d, J=12.9 Hz, 1H), 1.71 (d, J=12.4 Hz, 1H), 1.64-1.48 (m, 1H). LCMS: m/z=337 [M+H]⁺.

Step 4: (S)-Benzyl-2-(1-bromoimidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (4)

To a solution of compound 3 (69 mg, 0.2 mmol, 1.0 eq) in THF (1.5 mL), was added NBS (36 mg, 0.2 mmol, 1 eq) at 0° C. The mixture was stirred at 25° C. for 1 h, and then the mixture was diluted with water. It was extracted with EA. The organic layer was washed with sodium bicarbonate, water and brine. The solution was dried over Na₂SO₄, filtered and concentrated. The residue was purified with silica gel column chromatography (DCM/MeOH=100:1-50:1) to give 4 (60 mg, yield 75%).

¹H NMR (400 MHz, CDCl₃): δ 8.85 (s, 1H), 7.92 (s, 1H), 7.36 (s, 5H), 5.80 (s, 1H), 5.19 (s, 2H), 4.00 (d, J=13.4 Hz, 1H), 2.72 (dd, J=18.9, 7.5 Hz, 1H), 2.41 (dd, J=41.3, 13.3 Hz, 2H), 2.09-1.87 (m, 1H), 1.76 (dd, J=36.0, 13.0 Hz, 3H), 1.55 (dd, J=25.9, 12.9 Hz, 1H). LCMS: m/z=415 [M+H]⁺.

Step 5: (S)-Benzyl-2-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidine-1-carboxylate (5)

A mixture of 4 (60 mg, 0.15 mmol, 1.0 eq), (4-(2-fluoro-3-methoxyphenoxy)phenyl)boronic acid (57 mg, 0.22 mmol, 1.5 eq), PdCl₂(dppf) (11 mg, 0.015 mmol, 0.1 eq), and potassium carbonate (40 mg, 0.29 mmol, 2.0 eq) in dioxane (5.0 mL) and water (1.0 mL) was stirred under reflex overnight. The mixture was allowed to cool to room temperature. Water was added and the mixture was extracted with EA. The organic layer was washed with water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. He residue was purified by silica gel column chromatography (DCM/MeOH=100:1) to give the desired product 5 (66 mg, yield 82.5%).

¹H NMR (400 MHz, CDCl₃): δ 9.17 (s, 1H), 7.90 (d, J=7.1 Hz, 3H), 7.37 (s, 5H), 7.12 (d, J=7.1 Hz, 2H), 7.03 (t, J=8.2 Hz, 1H), 6.80 (t, J=7.4 Hz, 1H), 6.71 (t, J=6.9 Hz, 1H), 5.84 (s, 1H), 5.20 (s, 2H), 4.12 (d, J=5.6 Hz, 1H), 4.02 (d, J=12.7 Hz, 1H), 3.93 (s, 3H), 2.83 (t, J=13.0 Hz, 1H), 2.61 (s, 1H), 2.42 (d, J=12.5 Hz, 1H), 2.02 (d, J=17.3 Hz, 2H), 1.82 (d, J=12.5 Hz, 1H), 1.73 (d, J=9.0 Hz, 2H), 1.58 (d, J=12.0 Hz, 1H). LCMS: m/z=553 [M+H]⁺.

Step 6: (S)-1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)-3-(piperidin-2-yl)imidazo[1,5-a]pyrazine (6)

Compound 5 (66 mg, 0.12 mmol, 1.0 eq) was mixed with HBr/acetic acid (2.0 mL), and the mixture was stirred at room temperature (22° C.) for 2 h. Water was added and the pH of solution was adjusted to 7 with 2.0 M sodium hydroxide. The mixture was extracted with DCM. The organic layer was washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give the desired product 6 (50 mg, yield 100%). LCMS: m/z=419 [M+H]⁺.

Step 7: (S)-1-(2-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)piperidin-1-yl)prop-2-en-1-one (7)

To a solution of compound 6 (25 mg, 0.06 mmol, 1.0 eq) and TEA (9 mg, 0.09 mmol, 1.5 eq) in DCM (2.0 mL), was added acryloyl chloride (6 mg, 0.0 6 mmol, 1 eq). The mixture was stirred at 15° C. for 20 min. The mixture was diluted with water and extracted with DCM. The organic layer was washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated. The residue was purified with prep-TLC to give the desired product 7 (6 mg, yield 21.4%).

¹H NMR (400 MHz, CDCl₃): δ 9.19 (s, 1H), 8.10 (s, 1H), 7.91 (d, J=7.8 Hz, 2H), 7.50 (s, 1H), 7.12 (d, J=7.8 Hz, 2H), 7.03 (d, J=7.5 Hz, 1H), 6.81 (t, J=7.4 Hz, 1H), 6.72 (d, J=6.7 Hz, 1H), 6.67-6.51 (m, 1H), 6.38 (d, J=16.0 Hz, 2H), 5.77 (d, J=10.4 Hz, 1H), 3.94 (s, 3H), 3.78 (d, J=13.0 Hz, 1H), 3.09 (t, J=12.8 Hz, 1H), 2.81 (s, 1H), 2.47 (d, J=12.9 Hz, 1H), 2.02 (s, 1H), 1.84 (d, J=12.1 Hz, 2H), 1.76-1.50 (m, 3H). LCMS: m/z=473 [M+H]⁺.

Examples 7 to 34 were prepared following the procedures described above from Examples 1 to 6:

MS (cald.) [M + H]⁺/ Entry Structure MS (found) name 7

441.16/ 441.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 8

453.18/ 453.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 9

441.18/ 441.2 (S)-1-(2-(1-(4-(4- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 10

425.19/ 425.2 (S)-1-(2-(1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 11

429.16/ 429.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 12

439.21/ 439.2 (S)-1-(2-(1-(4-(2,3- dimethylphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 13

445.14/ 445.1 (S)-1-(2-(1-(2-chloro-4- phenoxyphenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 14

457.14/ 457.1 (S)-1-(2-(1-(2-chloro-4- phenoxyphenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 15

424.17/ 424.2 (S)-1-(2-(1-(6-phenoxypyridin-3- yl)imidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 16

441.18/ 441.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 17

475.13/ 475.1 (S)-1-(2-(1-(4-(3-chloro-2- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 18

437.19/ 437.2 (S)-1-(2-(1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 19

453.18/ 453.2 (S)-1-(2-(1-(4-(4- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 20

447.16/ 447.2 (S)-1-(2-(1-(4-(2,3- difluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 21

467.20/ 467.2 (S)-1-(2-(1-(4-(3-methoxy-2- methylphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 22

463.13/ 463.1 (S)-1-(2-(1-(4-(3-chloro-2- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 23

441.18/ 441.2 (S)-1-(2-(1-(4-(2- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 24

453.18/ 453.2 (S)-1-(2-(1-(4-(2- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 25

485.19/ 485.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 26

445.14/ 445.1 (S)-1-(2-(1-(3-chloro-4- phenoxyphenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 27

487.21/ 487.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 28

445.14/ 445.1 (S)-1-(2-(1-(4-(3- chlorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 29

455.20/ 455.2 (S)-1-(2-(1-(4-(3-methoxy-2- methylphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 30

459.18/ 459.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 31

540.23/ 540.2 (S,E)-2-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidine-1- carbonyl)-4,4-dimethylpent-2- enenitrile 32

495.21/ 495.2 (S)-3-(1-benzylpyrrolidin-2-yl)-1-(4- (2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine 33

476.17/ 476.2 (S)-2-(2-(1-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)-2- oxoacetamide 34

471.18/ 471.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 35

487.17/ 487.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- hydroxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 36

475.17/ 475.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- hydroxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 37

502.18/ 502.2 (S)-3-(1-acryloylpyrrolidin-2-yl)-1-(4- (2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine-8-carboxamide 38

514.18/ 514.2 (S)-3-(1-(but-2-ynoyl)pyrrolidin-2-yl)- 1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine-8-carboxamide 39

481.22/ 481.2 (S)-1-(2-(1-(4-(3- isopropoxyphenoxy)phenyl)imidazo [1,5-a]pyrazin-3-yl)pyrrolidin-1-yl) but-2-yn-1-one 40

453.22/ 453.2 (S)-1-(2-(8-methyl-1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)prop-2- en-1-one 41

465.22/ 465.2 (S)-1-(2-(8-methyl-1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 42

491.16/ 491.2 (S)-1-(2-(1-(4-(3-chloro-2- fluorophenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 43

503.16/ 503.2 (S)-1-(2-(1-(4-(3-chloro-2- fluorophenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 44

424.17/ 424.2 (S)-1-(2-(1-(5-phenoxypyridin-2- yl)imidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 45

443.18/ 443.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)prop-2- en-1-one 46

455.18/ 455.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 47

489.14/ 489.1 (S)-1-(2-(1-(4-(3-chloro-2- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 48

469.22/ 469.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 49

481.22/ 481.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 50

439.21/ 439.2 (S)-1-(2-(1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)prop-2- en-1-one 51

451.21/ 451.2 (S)-1-(2-(1-(4-(m- tolyloxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 52

467.20/ 467.2 (R)-1-(3-(1-(4-(3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 53

455.18/ 455.2 (R)-1-(3-(1-(4-(3- fluorophenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 54

457.14/ 457.1 (S)-1-(2-(1-(3-chloro-4- phenoxyphenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 55

457.20/ 457.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 56

469.20/ 469.2 (S)-1-(2-(1-(4-(3- fluorophenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 57

485.19/ 485.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 58

455.20/ 455.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)prop-2- en-1-one 59

467.20/ 467.2 (S)-1-(2-(1-(4-(3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 60

487.19/ 487.2 (S)-1-(2-(1-(4-(2,3- difluorophenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 61

473.19/ 473.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 62

473.19/ 473.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 63

485.19/ 485.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 64

487.21/ 487.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 65

499.21/ 499.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 66

531.20/ 531.2 methyl (S)-3-(1-acryloylpiperidin-2- yl)-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine-8-carboxylate 67

543.20/ 543.2 methyl (S)-3-(1-(but-2- ynoyl)piperidin-2-yl)-1-(4-(2-fluoro- 3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine-8-carboxylate 68

459.18/ 459.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 69

471.18/ 471.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 70

487.21/ 487.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 71

499.21/ 499.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 72

473.19/ 473.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 73

485.19/ 485.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 74

487.20/ 487.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 75

499.20/ 499.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 76

501.20/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 77

413.20/ 413.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 78

487.20/ 487.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 79

499.20/ 499.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 80

501.20/ 501.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)prop-2-en-1-one 81

513.20/ 513.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5,8- dimethylimidazo[1,5-a]pyrazin-3- yl)piperidin-1-yl)but-2-yn-1-one 82

489.20/ 489.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 83

473.20/ 473.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-6- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 84

473.20/ 473.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 85

489.19/ 489.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 86

501.19/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- methoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 87

425.22/ 425.2 (S)-1-(2-(8-cyclopropyl-1-(4-(2- fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 88

554.25/ 554.2 (R,E)-2-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidine-1-carbonyl)-4,4- dimethylpent-2-enenitrile 89

546.24/ 546.2 (R)-1-(3-(5-(2- (dimethylamino)ethoxy)-1-(4-(2- fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 90

558.24/ 558.2 (R)-1-(3-(5-(2- (dimethylamino)ethoxy)-1-(4-(2- fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 91

461.19/ 461.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)ethan-1-one 92

485.19/ 485.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 93

515.20/ 515.2 (R)-1-(3-(5-ethoxy-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 94

503.20/ 503.2 (R)-1-(3-(5-ethoxy-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 95

517.22/ 517.5 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- propoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 96

529.22/ 529.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- propoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 97

543.23/ 543.2 (R)-1-(3-(5-butoxy-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 98

545.21/ 545.2 1-((3R)-3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- ((tetrahydrofuran-3- yl)oxy)imidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 99

557.21/ 557.2 1-((3R)-3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- ((tetrahydrofuran-3- yl)oxy)imidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 100

529.22/ 529.2 (R)-1-(3-(5-cyclobutoxy-1-(4-(2- fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 101

541.22/ 541.2 (R)-1-(3-(5-cyclobutoxy-1-(4-(2- fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 102

567.27/ 567.2 (R)-3-(1-benzylpyrrolidin-3-yl)-5- butoxy-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine 103

545.21/ 545.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5-(2- methoxyethoxy)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 104

533.21/ 533.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5-(2- methoxyethoxy)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 105

556.26/ 556.2 (R,E)-4-(cyclopropyl(methyl)amino)- 1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-en-1-one 106

487.21/ 487.2 (R)-1-(3-(8-ethyl-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2- en-1-one 107

499.21/ 499.2 (R)-1-(3-(8-ethyl-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 108

514.18/ 514.2 (R)-3-(1-(but-2-ynoyl)pyrrolidin-3- yl)-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazine-8-carboxamide 109

501.22/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- propylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 110

513.22/ 513.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- propylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 111

501.22/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- isopropylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 112

513.22/ 513.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- isopropylimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 113

475.17/ 475.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- hydroxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 114

517.22/ 517.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- isopropoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)prop-2-en-1-one 115

429.22/ 429.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-5- isopropoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 116

501.19/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- methoxyimidazo[1,5-a]pyrazin-3- yl)pyrrolidin-1-yl)but-2-yn-1-one 117

415.20/ 415.2 (R)-1-(3-(8-ethoxy-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 118

543.20/ 543.2 (R)-(3-(1-(but-2-ynoyl)pyrrolidin-3- yl)-1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)imidazo[1,5- a]pyrazin-8-yl)methyl acetate 119

501.19/ 501.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- (hydroxymethyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one 120

503.18/ 503.2 (R)-1-(3-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- (fluoromethyl)imidazo[1,5-a]pyrazin- 3-yl)pyrrolidin-1-yl)but-2-yn-1-one 121

541.18/ 541.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- (trifluoromethyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)prop-2- en-1-one 122

553.18/ 553.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- (trifluoromethyl)imidazo[1,5- a]pyrazin-3-yl)piperidin-1-yl)but-2- yn-1-one 123

501.19/ 501.2 (S)-1-(2-(1-(4-(2-fluoro-3- methoxyphenoxy)phenyl)-8- (hydroxymethyl)imidazo[1,5- a]pyrazin-3-yl)pyrrolidin-1-yl)but-2- yn-1-one

Example 124 (S)-1-(2-(1-(4-((2,3-Difluorobenzyl)oxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (124)

Step 1: 2-(4-((2,3-Difluorobenzyl)oxy)phenyl)-4,4,5,5-tetramethyl-1,32-dioxaborolane (1)

A mixture of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenol (440 mg, 2 mmol, 1.0 eq), 1-(bromomethyl)-2,3-difluorobenzene (414 mg, 2 mmol, 1.0 eq) and Cesium carbonate (975 mg, 3 mmol, 1.5 eq) in acetonitrile (15.0 mL) was stirred at rt for 5 h. The solution was concentrated, and water was added. The mixture was extracted with EA. The organic layer was washed with sodium bicarbonate, water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give crude product 1 (835 mg).

Step 2: (S)-Benzyl-2-(1-(4-((2,3-difluorobenzyl)oxy)phenyl) imidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (3)

A mixture of 1 (100 mg, 0.25 mmol, 1.0 eq), 2 (130 mg, 0.375 mmol, 1.5 eq), PdCl₂(dppf) (18 mg, 0.025 mmol, 0.1 eq), and potassium carbonate (69 mg, 0.5 mmol, 2.0 eq) in dioxane (5.0 mL) and water (1.0 mL) was stirred under reflex overnight. The mixture was allowed to cool to room temperature. Water was added and the mixture was extracted with EA. The organic layer was washed with water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=100:1) to afford the desired product 3 (100 mg, yield 74.1%).

¹H NMR (400 MHz, CDCl₃): δ 9.08 (d, J=33.8 Hz, 1H), 7.83 (s, 2H), 7.60-7.39 (m, 2H), 7.32 (s, 4H), 7.10 (s, 6H), 6.89 (s, 1H), 5.45-4.71 (m, 6H), 3.92-3.51 (m, 2H), 2.78-2.22 (m, 3H), 2.11 (d, J=36.8 Hz, 1H). LCMS: m/z=541 [M+H]⁺.

Step 3: (S)-1-(4-((2,3-Difluorobenzyl)oxy)phenyl)-3-(pyrrolidin-2-yl)imidazo[1,5-a]pyrazine (4)

A solution of 3 (100 mg, 0.19 mmol, 1.0 eq) in DCM (2.0 mL) was mixed with 33% HBr/acetic acid (2 mL). The mixture was stirred at room temperature (22° C.) for 2 h. Water was added and the mixture was extracted with DCM. The pH of aqueous phase was adjusted to 8 with 2.0 M sodium hydroxide. The mixture was extracted with DCM, and the organic layer was washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give 4 (58 mg, yield 75.2%). LCMS: m/z=407 [M+H]⁺.

Step 4: (S)-1-(2-(1-(4-((2,3-Difluorobenzyl)oxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (5)

To a solution of 4 (29 mg, 0.07 mmol, 1.0 eq) and TEA (14 mg, 0.14 mmol, 2.0 eq) in DCM (2.0 mL), was added acryloyl chloride (6.3 mg, 0.07 mmol, 1.0 eq). The mixture was stirred at 15° C. for 20 min. The mixture was diluted with water and extracted with DCM. The organic layer was washed with water and brine. It was dried over Na₂SO₄, filtered and concentrated. The residue was purified with prep-TLC to give 5 (23.0 mg, yield 71.9%).

¹H NMR (400 MHz, CDCl₃): δ 9.11 (s, 1H), 8.33 (d, J=4.2 Hz, 1H), 7.82 (d, J=8.5 Hz, 2H), 7.55 (d, J=4.9 Hz, 1H), 7.30 (d, J=6.9 Hz, 1H), 7.21-7.00 (m, 4H), 6.45 (dd, J=16.8, 10.2 Hz, 1H), 6.39-6.24 (m, 1H), 5.68 (d, J=10.1 Hz, 1H), 5.61-5.43 (m, 1H), 5.21 (s, 2H), 3.90 (dd, J=13.3, 8.9 Hz, 1H), 3.74 (dd, J=17.0, 7.9 Hz, 1H), 2.84 (dd, J=19.4, 8.0 Hz, 1H), 2.56 (d, J=4.5 Hz, 1H), 2.31 (td, J=16.2, 8.1 Hz, 1H), 2.26-2.08 (m, 1H). LCMS: m/z=461 [M+H]⁺.

Example 125 (S)-(2-(1-(4-((2-fluorophenoxy)methyl)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (125)

Step 1: 2-(4-((2-Fluorophenoxy)methyl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1)

A suspension of 2-(4-(bromomethyl)phenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.0 g, 3.37 mmol, 1.0 eq), 2-fluorophenol (415 mg, 3.70 mmol, 1.1 eq) and Cesium carbonate (1.43 g, 4.38 mmol, 1.3 eq) in acetonitrile (20 mL) was stirred at rt for 5 h. The mixture was mixed with water (50 mL) and extracted with EA. The combined organic layers were washed with sodium bicarbonate, water, and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give crude product 1 (1.3 g), which was used into next reaction without further purification.

¹H NMR (400 MHz, CDCl₃): δ 7.81 (d, J=7.2 Hz, 2H), 7.43 (d, J=7.2 Hz, 2H), 7.11-7.06 (m, 1H), 6.99-6.88 (m, 3H), 5.16 (s, 2H), 1.34 (s, 12H).

Step 2: (S)-benzyl 2-(1-(4-((2-fluorophenoxy)methyl)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (2)

A mixture of compound 1 (148 mg, 0.45 mmol, 1.5 eq), (S)-benzyl 2-(1-bromoimidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (120 mg, 0.30 mmol, 1.0 eq), PdCl₂(dppf) (22 mg), and potassium carbonate (83 mg, 0.60 mmol, 2.0 eq) in dioxane (10 mL) and water (2.0 mL) was stirred under reflux for 3 h. The mixture was allowed to cool to room temperature. Water was added and the mixture was extracted with EA. The combined organic layers were washed with water and brine. The solution was dried over anhydrous sodium sulfate. The solvent was removed in vacuum and the residue was purified by silica gel column chromatography (PE/EA=2:1-1:2) to afford the desired product 2 (110 mg, yield 72%).

¹H NMR (400 MHz, CDCl₃): δ 9.18-9.09 (m, 1H), 8.25 (s, 0.5H), 7.91 (s, 2H), 7.66-7.46 (m, 4H), 7.33-7.26 (m, 3H), 7.25-7.02 (m, 4H), 6.98-6.90 (m, 2H), 5.33-5.21 (m, 3H), 5.20-4.81 (m, 2H), 3.78-3.67 (m, 2H), 2.54-2.35 (m, 3H), 2.08-2.07 (m, 1H). LCMS: m/z=509 [M+H]⁺.

Step 3: (S)--(4-((2-Fluorophenoxy)methyl)phenoxy)methyl)phenyl)-3-(pyrrolidin-2-yl)imidazo[1,5-a]pyrazine (3)

A solution of compound 2 (107 mg, 0.20 mmol, 1.0 eq) in DCM (2.0 mL) was mixed with 33% HBr/acetic acid (2.0 mL). The mixture was stirred at room temperature (22° C.) for 1 h. Water was added and the mixture was extracted with DCM. The pH of the aqueous phase was adjusted to 8 with ammonium hydroxide. The mixture was extracted with DCM, and the organic layer was washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give 3 (65 mg), which was used into next reaction without further purification. LCMS: m/z=375 [M+H]⁺.

Step 4: (S)-1-(2-(1-(4-((2-Fluorophenoxy)methyl)phenyl) imidazo[1,5-a]pyrazin-3-yl)pyrrolidin-1-yl)prop-2-en-1-one (4)

To a solution of compound 3 (32 mg, 0.084 mmol, 1.0 eq) and TEA (0.02 mL) in DCM (5.0 mL), was added acryloyl chloride (7.6 mg, 0.084 mmol, 1.0 eq). The mixture was stirred at 15° C. for 30 min. The mixture was quenched with methanol (2.0 mL) and the solvent was removed in vacuo. The residue was purified with prep-TLC to give 4 (10.4 mg, yield 28%).

¹H NMR (400 MHz, CDCl₃): δ 9.17 (s, 1H), 8.36 (d, J=4.0 Hz, 1H), 7.90 (d, J=8.0 Hz, 2H), 7.59-7.53 (m, 3H), 7.12-7.01 (m, 3H), 6.90-6.62 (m, 1H), 6.48-6.42 (m, 1H), 6.33-6.29 (m, 1H), 5.69-5.66 (m, 1H), 5.56-5.53 (m, 1H), 5.20 (s, 2H), 3.90-3.88 (m, 1H), 3.74-3.72 (m, 1H), 2.91-2.82 (m, 1H), 2.64-2.58 (m, 1H), 2.38-2.25 (m, 1H), 2.20-2.16 (m, 1H). LCMS: m/z=429 [M+H]⁺.

Examples 126 to 163 were prepared following the procedures described above for Examples 124 and 125:

MS (cald.) [M+H]⁺/ Entry structure MS (found) name 126

443.18/443.2 (S)-1-(2-(1-(4-((4- fluorophenoxy)methyl) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 127

473.17/473.2 (S)-1-(2-(1-(4-((2,3- difluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 128

455.18/455.2 (S)-1-(2-(1-(4-((4- fluorophenoxy)methyl) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 129

461.17/461.2 (S)-2-(2-(1-(4-((2,3- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)prop- 2-en-l-one 130

473.17/473.2 (S)-1-(2-(1-(4-((2,3- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)but- 2-yn-1-one 131

461.17/461.2 (S)-1-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)prop- 2-en-1-one 132

473.17/473.2 (S)-l-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)but- 2-yn-1-one 133

461.17/461.2 (S)-1-(2-(1-(4-((3,4- difluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 134

473.17/473.2 (S)-1-(2-(1-(4-((3,4- difluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 135

443.18/443.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 136

461.17/461.2 (S)-1-(2-(1-(4-((2,6- difluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 137

473.17/473.2 (S)-1-(2-(1-(4-((2,6- difluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)bul-2-yn-1-one 138

455.18/455.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 139

471.21/471.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)prop-2-en-1-one 140

483.21/483.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)but-2-yn-1-one 141

459.15/459.2 (S)-1-(2-(1-(4-((3- chlorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 142

471.15/471.2 (S)-1-(2-(1-(4-((3- chlorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 143

425.19/425.2 (S)-1-(2-(1-(4- (phenoxymethyl) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)prop-2-en-1-one 144

437.19/437.2 (S)-1-(2-(1-(4- (phenoxymethyl) phenyl)imidazo[1,5-a] pyrazin-3-yl)pyrrolidin- 1-yl)but-2-yn-1-one 145

443.18/443.2 (S)-1-(2-(1-(4-((3- fluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)prop- 2-en-1-one 146

455.18/455.2 (S)-1-(2-(1-(4-((2- fluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)but- 2-yn-1-one 147

455.18/455.2 (S)-1-(2-(1-(4-((3- fluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)but- 2-yn-1-one 148

475.19/475.2 (S)-1-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) piperidin-1-yl)prop- 2-en-1-one 149

487.19/487.2 (S)-1-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) piperidin-1-yl)but- 2-yn-1-one 150

489.20/489.2 (S)-1-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)prop-2-en-1-one 151

501.20/501.2 (S)-1-(2-(1-(4-((3,4- difluorophenoxy) methyl)phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)but-2-yn-1-one 152

457.20/457.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)prop-2-en-1-one 153

469.20/469.2 (S)-1-(2-(1-(4-((3- fluorobenzyl)oxy) phenyl)imidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)but-2-yn-1-one 154

489.20/489.2 (S)-1-(2-(1-(4-((2,3- difluorobenzyl)oxy) phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)prop-2-en-1-one 155

501.20/501.2 (S)-1-(2-(1-(4-((2,3- difluorobenzyl)oxy) phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)but-2-yn-1-one 156

471.21/471.2 (S)-1-(2-(1-(4-((3- fluorophenoxy)methyl) phenyl)-8- methylimidazo[1,5-a] pyrazin-3-yl)piperidin- 1-yl)prop-2-en-1-one 157

483.21/483.2 (S)-1-(2-(1-(4-((3- fluorophenoxy)methyl) phenyl)-8-methylimidazo [1,5-a]pyrazin-3-yl) piperidin-1-yl)but-2-yn-1-one 158

475.19/475.2 (S)-1-(2-(1-(4-((2,3- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) piperidin-1-yl)prop-2- en-1-one 159

487.19/487.2 (S)-1-(2-(1-(4-((2,3- difluorophenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) piperidin-1-yl)but- 2-yn-1-one 160

485.19/485.2 (S)-1-(2-(1-(4-((2- fluoro-3- methoxyphenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)but-2- yn-1-one 161

473.19/473.2 (S)-1-(2-(1-(4-((2- fluoro-3- methoxyphenoxy) methyl)phenyl)imidazo [1,5-a]pyrazin-3-yl) pyrrolidin-1-yl)prop- 2-en-1-one 162

521.21/521.2 (S)-1-(2-(8-methyl-1- (3-((3-(trifluoromethyl) benzyl)oxy)phenyl) imidazo[1,5-a]pyrazin- 3-yl)piperidin-1-yl)prop- 2-en-1-one 163

533.21/533.2 (S)-1-(2-(8-methyl-1- (3-((3-(trifluoromethyl) benzyl)oxy)phenyl) imidazo[1,5-a]pyrazin- 3-yl)piperidin-1-yl)but- 2-yn-1-one

Example 164 (S)-4-(3-(1-(But-2-ynoyl)pyrrolidin-2-yl)imidazo[1,5-a]pyrazin-1-yl)-N-(2-fluoro-3-methoxyphenyl)benzamide (164)

Step 1: 4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)benzoyl chloride (1)

To a solution of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoic acid (1.0 g, 4.03 mmol, 1.0 eq) and 2 drops of DMF in DCM (20 mL), was added oxalyl chloride (1.0 mL, 10.08 mmol, 2.5 eq) slowly for 40 min. The mixture was stirred at room temperature for 4 h. The solution was concentrated to give the desired product 1 (1.2 g), which was used into next reaction without further purification.

Step 2: N-(2-Fluoro-3-methoxyphenyl)-4-(4,4,5,5-tetramethyl-1,3-dioxolan-2-yl)benzamide (2)

To a solution of compound 1 (697 mg, 2.61 mmol, 1.0 eq) in CH₃CN (10.0 mL), was added 2-fluoro-3-methoxyaniline (406 mg, 2.88 mmol, 1.1 eq) in CH₃CN (10.0 mL). The mixture was stirred at rt for 14 h. The volume of reaction mixture was reduced into 1/3, and 3% citric acid solution (50 mL) was added. The mixture was extracted with DCM, and the organic layer was washed with 3% citric acid solution and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give the desired product 2 as a white solid (0.93 g, yield 61.8%), which was used into next reaction without further purification.

Step 3: (S)-Benzyl-2-(1-(4-((2-fluoro-3-methoxyphenyl)carbamoyl)phenyl)imidazo[1,5-a]pyrazin-3-yl)pyrrolidine-1-carboxylate (4)

A mixture of compound 2 (352 mg, 0.95 mmol, 2.0 eq), compound 3 (190 mg, 0.475 mmol, 1.0 eq), Pd[PPh₃]₄ (40 mg), and Cesium carbonate (361 mg, 0.95 mmol, 2.0 eq) in dioxane (7.0 mL) and water (1.0 mL) was stirred under reflex for 5 h. The mixture was allowed to cool to room temperature, and water was added. It was extracted with EA. The combined organic layers were washed water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=100:1) to give the desired product 4 (340 mg). LCMS: m/z=566 [M+H]⁺.

Step 4: (S)-N-(2-Fluoro-3-methoxyphenyl)-4-(3-(pyrrolidin-2-yl)imidazo[1,5-a]pyrazin-1-yl)benzamide (5)

A solution of compound 4 (340 mg) was in DCM (10.0 mL) was mixed with 33% HBr/acetic acid (2.0 mL), and the mixture was stirred at room temperature (20° C.) for 2 h. Water was added and the mixture was extracted with DCM. The pH of the aqueous phase was adjusted to 8 with 2.0 M sodium hydroxide. The mixture was extracted with DCM, and the combined organic layers were washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated to give the desired product 5 (140 mg, yield 68.4%).

¹H NMR (400 MHz, CDCl₃): δ 9.27 (s, 1H), 8.16-8.02 (m, 7H), 7.57 (d, J=4.8 Hz, 1H), 7.15-7.10 (m, 1H), 6.80-6.76 (m, 1H), 4.69-4.65 (m, 1H), 3.93 (s, 3H), 3.24-3.22 (m, 1H), 3.10-3.07 (m, 1H), 2.32-2.27 (m, 2H), 2.04-1.96 (m, 2H). LCMS: m/z=432 [M+H]⁺.

Step 5: (S)-4-(3-(1-(But-2-ynoyl)pyrrolidin-2-yl)imidazo[1,5-a]pyrazin-1-yl)-N-(2-fluoro-3-methoxyphenyl)benzamide (6)

To a solution of compound 5 (20 mg, 0.046 mmol, 1.0 eq) and TEA (14 mg, 0.139 mmol, 3.0 eq) in DCM (4.0 mL), were added but-2-ynoic acid (3.9 mg, 0.046 mmol, 1.0 eq) and HATU (17.6 mg 0.046 mmol, 1.0 eq). The mixture was stirred at 15° C. for 40 min. The mixture was diluted with water and it was extracted with DCM. The combined organic layers were washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated. The residue was purified with prep-TLC to give the desired product 6 (11 mg, yield 47.7%).

¹H NMR (400 MHz, CDCl₃): δ 9.23 (s, 1H), 8.37 (d, J=4.8 Hz, 1H), 8.15 (s, 1H), 8.10-7.99 (m, 5H), 7.61 (d, J=4.8 Hz, 1H), 7.14-7.10 (m, 1H), 6.80-6.76 (m, 1H), 5.51-5.49 (m, 1H), 3.92 (s, 3H), 3.90-3.86 (m, 2H), 2.75-2.66 (m, 2H), 2.39-2.34 (m, 1H), 2.17-2.14 (m, 1H), 1.98 (s, 2.5H), 1.64 (s, 0.5H). LCMS: m/z=498 [M+H]⁺.

Examples 165 and 215 were prepared following the procedure described for Example 164:

MS (cald.) [M+H]⁺/ Entry Structure MS (found) name 165

486.19/486.2 (S)-4-(3-(1- acryloylpyrrolidin-2- yl)imidazo[1,5-a]pyrazin- 1-yl)-N-(2-fluoro-3- methoxyphenyl)benzamide 166

451.18/451.2 (S)-4-(3-(1-(but-2- ynoyl)pyrrolidin-2- yl)imidazo[1,5-a]pyrazin- 1-yl)-N-(pyridin-2-yl) benzamide 167

465.20/465.2 (R)-4-(3-(1-(but-2-ynoyl) piperidin-3-yl)imidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 168

453.20/453.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)imidazo[1,5-a]pyrazin- 1-yl)-N-(pyridin-2-yl) benzamide 169

465.20/465.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)imidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 170

467.21/467.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-8-methylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 171

479.21/479.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-8- methylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 172

453.20/453.2 (S)-4-(3-(1-aeryloylpyrrolidin- 2-yl)-5-methylimidazo [1,5-a]pyrazin-l-yl)-N- (pyridin-2-yl)benzamide 173

465.20/465.2 (S)-4-(3-(1-(but-2-ynoyl) pyrrolidin-2-yl)-5- methylimidazo[1,5-a]pyrazin-1- yl)-N-(pyridin-2-yl)benzamide 174

467.21/467.2 (S)-4-(3-(1-acryloylpyrrolidin- 2-yl)-5,8-dimethylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 175

479.21/479.2 (S)-4-(3-(1-(but-2-ynoyl) pyrrolidin-2-yl)-5,8- dimethylimidazo[1,5-a] pyrazin-1-yl)-N-(pyridin- 2-yl)benzamide 176

439.18/439.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)imidazo[1,5-a]pyrazin- 1-yl)-N-(pyridin-2-yl)benzamide 177

451.18/451.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)imidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 178

467.21/467.2 (R)-4-(3-(1-acryloylpiperidin- 3-yl)-5-methylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 179

479.21/479.2 (R)-4-(3-(1-(but-2-ynoyl) piperidin-3-yl)-5- methylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 180

453.20/453.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)-5-methylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 181

465.20/465.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5- methylimidazo[1,5-a]pyrazin-1- yl)-N-(pyridin-2-yl)benzamide 182

467.20/467.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)-5,8-dimethylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 183

479.20/479.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5,8- dimethylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 184

481.20/481.2 (R)-4-(3-(1-acryloylpiperidin- 3-yl)-5,8-dimethylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 185

493.20/493.2 (R)-4-(3-(1-(but-2-ynoyl) piperidin-3-yl)-5,8- dimethylimidazo[1,5-a]pyrazin- 1-yl)-N-(pyridin-2-yl)benzamide 186

467.20/467.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-5-methylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 187

479.20/479.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-5- methylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 188

481.20/481.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-5,8-dimethylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 189

493.20/493.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-5,8- dimethylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 190

479.21/479.2 (S)-4-(3-(1-acryloylpyrrolidin- 2-yl)-8-cyclopropylimidazo [1,5-a]pyrazin-l-yl)- N-(pyridin-2-yl)benzamide 191

493.23/493.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-8-cyclopropylimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 192

505.23/505.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-8- cyclopropylimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 193

495.21/495.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5- ethoxyimidazo[1,5-a] pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 194

483.21/483.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)-5-ethoxyimidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 195

507.17/507.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)imidazo[1,5-a] pyrazin-1-yl)-N-(4- (trifluoromethyl) pyridin-2-yl)benzamide 196

563.19/563.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5- ethoxyimidazo[1,5-a]pyrazin- 1-yl)-N-(4- (trifluoromethyl)pyridin- 2-yl)benzamide 197

569.18/569.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)-5-ethoxyimidazo [1,5-a]pyrazin-1-yl)-3- fluoro-N-(4-(trifluoromethyl) pyridin-2-yl)benzamide 198

581.18/581.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5- ethoxyimidazo[1,5-a]pyrazin- 1-yl)-3-fluoro-N-(4- (trifluoromethyl)pyridin- 2-yl)benzamide 199

521.18/521.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-8-(trifluoromethyl) imidazo[1,5-a]pyrazin-1-yl)- N-(pyridin-2-yl)benzamide 200

533.18/533.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-8- (trifluoromethyl)imidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 201

589.17/589.2 (S)-4-(3-(1-acryloylpiperidin- 2-yl)-8-(trifluoromethyl) imidazo[1,5-a]pyrazin-1-yl)-N- (4-(trifluoromethyl)pyridin-2- yl)benzamide 202

601.17/601.2 (S)-4-(3-(1-(but-2-ynoyl) piperidin-2-yl)-8- (trifluoromethyl)imidazo [1,5-a]pyrazin-1-yl)-N-(4- (trifluoromethyl)pyridin-2- yl)benzamide 203

563.19/563.2 (S)-4-(3-(1-(but-2-ynoyl) pyrrolidin-2-yl)-5-ethoxyimidazo [1,5-a]pyrazin-1- yl)-N-(4-(trifluoromethyl) pyridin-2-yl)benzamide 204

551.19/551.2 (S)-4-(3-(1-acryloylpyrrolidin- 2-yl)-5-ethoxyimidazo [1,5-a]pyrazin-1-yl)-N- (4-(trifluoromethyl)pyridin-2- yl)benzamide 205

509.22/509.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)-5-ethoxy-8- methylimidazo[1,5-a] pyrazin-1-yl)-N-(pyridin-2- yl)benzamide 206

497.22/497.2 (R)-4-(3-(1-acryloylpyrrolidin- 3-yl)-5-ethoxy-8- methylimidazo[1,5-a]pyrazin- 1-yl)-N-(pyridin-2-yl)benzamide 207

481.19/481.2 (S)-4-(3-(1-(but-2-ynoyl) pyrrolidin-2-yl)-8- (hydroxymethyl)imidazo [1,5-a]pyrazin-1-yl)-N- (pyridin-2-yl)benzamide 208

567.17/567.2 (S)-4-(3-(1-(but-2-ynoyl) pyrrolidin-2-yl)-8- (hydroxymethyl)imidazo [1,5-a]pyrazin-1-yl)-3-fluoro- N-(4-(trifluoromethyl) pyridin-2-yl)benzamide 209

523.18/523.2 (S)-4-(8-(fluoromethyl)- 3-(1-(prop-1-yn-1-yl) pyrrolidin-2-yl)imidazo [1,5-a]pyrazin-1-yl)-N-(4- (trifluoromethyl) pyridin-2-yl)benzamide 210

521.18/521.2 (S)-4-(8-(hydroxymethyl)- 3-(1-(prop-1-yn-1-yl) pyrrolidin-2-yl)imidazo [1,5-a]pyrazin-1-yl)-N-(4- (trifluoromethyl) pyridin-2-yl)benzamide 211

519.17/519.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)imidazo[1,5-a] pyrazin-1-yl)-N-(4- (trifluoromethyl) pyridin-2-yl)benzamide 212

537.16/537.2 (R)-4-(3-(1-(but-2-ynoyl) pyrrolidin-3-yl)imidazo [1,5-a]pyrazin-1-yl)-3-fluoro- N-(4-(trifluoromethyl) pyridin-2-yl)benzamide

Example 213 (6R)-6-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)hexahydroindolizin-3(2H)-one (213)

Step 1: 6-((3-Chloropyrazin-2-yl)glycyl)hexahydroindolizin-3(2H)-one (1)

A mixture of SM (1.4 g, crude, 7.8 mmol), (3-chloropyrazin-2-yl)methanamine hydrochloride (1.4 g, 7.8 mmol), HATU (2.7 mg, 7.8 mmol) and TEA (3.2 mg, 31.2 mmol) in DCM (30 mL) was stirred at 25° C. overnight. The mixture was quenched with H₂O (60 mL) and it was extracted with DCM (25 mL×3). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated to give a crude product. The crude product was purified by prep-TLC to give 1 (1.3 g, 50%). LCMS: m/z=309 [M+H]⁺.

Step 2: 6-(8-Chloroimidazo[1,5-a]pyrazin-3-yl)hexahydroindolizin-3(2H)-one (2)

To a solution of compound 1 (700 mg, 2.3 mmol) in acetonitrile (15 ml) and 1,3-dimethyl-2-imidazolidinone (777 mg, 6.8 mmol) at 0° C., POCl₃ (1.4 g, 9.1 mmol) was added dropwise while the temperature remained around 15° C. Then the reaction mixture was refluxed at 80° C. overnight. The solvent was removed and water (150 mL) was added. The pH of aqueous layer was adjusted to 8-9 and the mixture was extracted with ethyl acetate (40 mL×3). The combined organic layers were washed with brine, dried over sodium sulfate, and filtered. The solvent was removed under vacuum. The residue was purified using prep-TLC to give 2 (130 mg, 20%). LCMS: m/z=291 [M+H]⁺.

Step 3: 6-(Imidazo[1,5-a]pyrazin-3-yl)hexahydroindolizin-3(2H)-one (3)

The mixture of 1 (93 mg, 0.32 mmol), triphenylphosphine (13 mg, 0.05 mmol), Pd(OAc)₂ (7 mg, 0.03 mmol) and potassium carbonate (88 mg, 0.64 mmol) in n-butanol (5.0 mL) was stirred at 130° C. for 2 h under N₂ atmosphere. The reaction mixture was concentrated and the residue was purified by prep-TLC to give 3 (50 mg, 61%).

¹H NMR (400 MHz, CDCl₃): δ 8.94 (s, 1H), 7.76 (d, J=4.0 Hz, 2H), 7.54 (d, J=3.6 Hz, 1H), 4.38 (d, J=12.0 Hz, 1H), 3.67-3.59 (m, 1H), 3.14-2.96 (m, 2H), 2.47 (t, J=7.6 Hz, 2H), 2.35-2.27 (m, 1H), 2.23-2.15 (m, 2H), 2.14-2.07 (m, 2H), 1.77-1.64 (m, 1H), 1.50-1.35 (m, 1H), 1.29-1.21 (m, 1H). LCMS: m/z=257 [M+H]⁺.

Step 4: 6-(8-Bromoimidazo[1,5-a]pyrazin-3-yl)hexahydroindolizin-3(2H)-one (4)

To a solution of 3 (45 mg, 0.176 mmol) in THF (10.0 mL) was added NBS (31 mg, 0.176 mmol). The solution was stirred at rt for 2 h. The solvent was removed in vacuum and the residue was purified by prep-TLC to give 4(46 mg, 78%).

¹H NMR (400 MHz, CDCl₃): δ 8.87 (s, 1H), 7.69 (d, J=4.0 Hz, 1H), 7.60 (d, J=3.6 Hz, 1H), 4.46-4.29 (m, 1H), 3.65-3.52 (m, 1H), 3.08-2.93 (m, 2H), 2.47 (t, J=8.0 Hz, 2H), 2.36-2.27 (m, 1H), 2.20-2.13 (m, 2H), 2.12-2.06 (s, 1H), 1.75-1.65 (m, 1H), 1.52-1.33 (m, 1H). LCMS: m/z=334/336 [M+H]⁺.

Step 5: 6-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)hexahydroindolizin-3(2H)-one (5)

A mixture of 4 (40 mg, 0.12 mmol,), (4-(2-fluoro-3-methoxyphenoxy)phenyl)boronic acid (63 mg, 0.24 mmol,), PdCl₂(dppf) (9 mg), and potassium carbonate (33 mg, 0.012 mmol,) in dioxane (5.0 mL) and water (1.0 mL) was stirred under reflux for 3 h. The mixture was concentrated and the residue was purified by prep-TLC to give 5 (29 mg, 51%).

¹H NMR (400 MHz, CDCl₃): δ 9.16 (s, 1H), 7.84 (d, J=8.4 Hz, 2H), 7.68 (d, J=4.0 Hz, 1H), 7.54 (s, 1H), 7.12 (d, J=8.4 Hz, 2H), 7.03 (t, J=7.6, 2.0 Hz, 1H), 6.84-6.76 (m, 1H), 6.73-6.67 (m, 1H), 4.49-4.38 (m, 1H), 3.94 (s, 3H), 3.70-3.60 (m, 1H), 3.61-3.05 (m, 2H), 2.48 (t, J=8.4 Hz, 2H), 2.37-2.26 (m, 1H), 2.25-2.19 (m, Hz, 2H), 2.14-2.08 (m, 1H), 1.76-1.67 (m, 1H), 1.50-1.39 (m, 1H). LCMS: m/z=473 [M+H]⁺.

Example 214 7-(1-(4-(2-fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)-2-methyloctahydro-1H-pyrido[1,2-c]pyrimidin-1-one (214)

Step 1: Methyl 6-vinylnicotinate (1)

To a solution of methyl 6-bromonicotinate (10 g, 46.5 mmol) in i-PrOH (100 mL) were added potassium vinyltrifluoroborate (12.4 g, 93 mmol), Et₃N (14.1 g, 140 mmol), and Pd(dppf)Cl₂-DCM (1.1 g). The mixture was stirred at 100° C. for 2 h under nitrogen. The reaction was complete monitored by TLC. The mixture was concentrated and the residue was purified by column chromatography on silica gel eluted with PE/EA=15/1 to give methyl 6-vinylnicotinate 1 (7.2 g, 95%).

¹H NMR (400 MHz, CDCl₃): δ 9.15 (d, J=1.56 Hz, 1H), 8.23 (dd, J=8.22, 2.35 Hz, 1H), 7.39 (d, J=8.22 Hz, 1H), 6.85 (dd, J=17.41, 10.76 Hz, 1H), 6.36 (d, J=20.0 Hz, 1H), 5.55 (d, J=12.0 Hz, 1H), 3.94 (s, 3H).

Step 2: Methyl 6-(2-((2,4-dimethoxybenzyl)amino)ethyl)nicotinate(2)

To a solution of methyl 6-vinylnicotinate 1 (2.0 g, 12.3 mmol) in MeOH (15 mL) were added (2,4-dimethoxyphenyl)methanamine (4.08 g, 24.5 mmol) and AcOH (15 mL). The mixture was heated to reflux overnight. The mixture was concentrated, basified with aq. NaHCO₃ and extracted with EA. The organic layer was dried and concentrated. The residue was purified by column chromatography on silica gel eluted with PE/EA=3/1 to give methyl 6-(2-((2,4-dimethoxybenzyl)amino)ethyl)nicotinate 2 (2.6 g, 64%).

¹H NMR (400 MHz, CDCl₃): δ 9.11 (d, J=1.56 Hz, 1H), 8.18 (dd, J=8.22, 2.35 Hz, 1H), 7.26 (d, J=8.22 Hz, 1H), 7.09 (dd, J=17.41, 10.76 Hz, 1H), 6.41 (m, 2H), 3.94 (s, 3H), 3.78 (s, 3H), 3.76 (s, 3H), 3.74 (s, 2H), 3.05-3.00 (m, 4H). LCMS: m/z=331 [M+H]⁺.

Step 3: Methyl 6-(2-((2,4-dimethoxybenzyl)amino)ethyl)piperidine-3-carboxylate (3)

To a solution of compound 2 (2.5 g, 7.6 mmol) in AcOH (40 mL) was added NaBH₃CN (1.9 g, 30.3 mmol). The mixture was stirred at room temperature for 1 h, and then heated to 70° C. overnight. The solvent was evaporated and the residue was dissolved in MeOH. The solution was alkalified with NaHCO₃ solution. The solvent was removed and the mixture was extracted with DCM. The organic layer was dried over sodium sulfate and concentrated. The residue was purified by column chromatography on silica gel eluted with DCM/MeOH=20/1 to give methyl 6-(2-((2,4-dimethoxybenzyl)amino)ethyl)piperidine-3-carboxylate 3 (1.2 g). LCMS: m/z=337 [M+H]⁺.

Step 4: Methyl 2-(2,4-dimethoxybenzyl)-1-oxooctahydro-1H-pyrido[1,2-c]pyrimidine-7-carboxylate (4)

To a solution of compound 3 (1.5 g, crude, 1.0 eq) in THF (20 mL) was added CDI (1.45 g, 2.0 eq). The reaction mixture was stirred at 70° C. overnight, and then it was allowed to cool to room temperature. Water was added and the mixture was extracted with EA. The combined organic layers were washed with water and brine. The solution was dried over anhydrous Na₂SO₄, filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH=100:1) to afford the desired product 4 (400 mg, yield 25%).

¹H NMR (400 MHz, CDCl₃): δ 7.19 (m, 1H), 6.46-6.44 (m, 2H), 4.80 (d, J=12.8 Hz, 1H), 4.55-4.41 (m, 2H), 3.79 (s, 6H), 3.67 (s, 3H), 3.21-3.18 (m, 3H), 2.64-2.58 (m, 1H), 2.49-2.43 (m, 1H), 2.12-2.00 (m, 2H), 1.96-1.70 (m, 2H), 1.68-1.66 (m, 1H), 1.58-1.57 (m, 1H). LCMS: m/z=363 [M+H]⁺.

Step 5: 2-Methyl-1-oxooctahydro-1H-pyrido[1,2-c]pyrimidine-7-carboxylic acid (5)

A solution of compound 4 (400 mg, 1.06 mmol) in TFA (5.0 mL) was stirred at 90° C. for 2 h. The solvent was removed and the residue was suspended in dry THF (20 mL), followed by addition of NaH (220 mg, 5.5 mmol) in an ice water bath. The mixture was stirred at room temperature for 30 min and then MeI (776 mg, 5.5 mmol) was added dropwise. The reaction was stirred at room temperature overnight and quenched with water. The pH of the mixture was adjusted to 2 with concentrated hydrochloric acid and the mixture was extracted with ethyl acetate. The organic layer was washed with water and brine. The solution was dried over Na₂SO₄, filtered and concentrated. The crude product 5 (160 mg) was used for next step without purification.

¹H NMR (400 MHz, CDCl₃): δ 8.04 (br, 2H), 4.70-4.67 (m, 1H), 3.25-3.19 (m, 3H), 2.91 (s, 3H), 2.63-2.61 (m, 1H), 2.44-2.42 (m, 1H), 2.16-2.08 (m, 3H), 1.79-1.76 (m, 2H), 1.62-1.51 (m, 1H), 1.35-1.26 (m, 1H). LCMS: m/z=213 [M+H]⁺.

Step 6: N-((3-Chloropyrazin-2-yl)methyl)-2-methyl-1-oxooctahydro-1H-pyrido[1,2-c]pyrimidine-7-carboxamide (6)

A mixture of compound 5 (270 mg, 1.28 mmol), (3-chloropyrazin-2-yl)methanamine hydrochloride (277 mg, 1.54 mmol), HATU (632 mg, 1.66 mmol) and TEA (518 mg, 5.12 mmol) in DCM (13 mL) was stirred at 25° C. overnight. The mixture was quenched with H₂O (40 mL) and extracted with DCM (15 mL×3). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by prep-TLC to give 6 (130 mg, 30%).

¹H NMR (400 MHz, CDCl₃): δ 8.45 (s, 1H), 8.32 (s, 1H), 7.06 (s, 2H), 4.74-4.69 (m, 3H), 3.23-3.22 (m, 3H), 2.93 (s, 3H), 2.74-2.71 (m, 1H), 2.53-2.40 (m, 1H), 2.13-2.02 (m, 2H), 1.81-1.77 (m, 2H). LCMS: m/z=338 [M+H]⁺.

Step 7: 7-(8-Chloroimidazo[1,5-a]pyrazin-3-yl)-2-methyloctahydro-1H-pyrido[1,2-c]pyrimidin-1-one (7)

To a solution of compound 6 (130 mg, 0.38 mmol), and 1,3-dimethyl-2-imidazolidinone (130 mg, 1.14 mmol) in acetonitrile (10 ml) at 0° C., POCl₃ (236 mg, 1.54 mmol) was added dropwise while the temperature remained around 5° C. The reaction mixture was refluxed at 80° C. overnight. The reaction mixture was concentrated and water (15 mL) was added. The pH of aqueous layer was adjusted to 8-9 and the mixture was extracted with ethyl acetate (20 mL×3). The combined organic layers were washed with brine, dried over sodium sulfate, and filtered. The solvent was removed. The residue was purified using prep-TLC to give 7 (60 mg, 49%).

¹H NMR (400 MHz, CDCl₃): δ 7.87 (d, J=4.8 Hz, 1H), 7.78 (s, 1H), 7.34 (d, J=4.8 Hz, 1H), 4.76-4.75 (m, 1H), 3.46-3.42 (m, 1H), 3.39-3.30 (m, 2H), 3.14-3.10 (m, 1H), 2.97 (s, 3H), 2.74-2.68 (m, 1H), 2.24-2.20 (m, 3H), 1.95-1.91 (m, 1H), 1.88-1.83 (m, 1H), 1.57-1.52 (m, 1H). LCMS: m/z=320 [M+H]⁺.

Step 8: 7-(Imidazo[1,5-a]pyrazin-3-yl)-2-methyloctahydro-1H-pyrido[1,2-c]pyrimidin-1-one (8)

A mixture of compound 7 (60 mg, 0.19 mmol), triphenylphosphine (10 mg, 0.04 mmol), Pd(OAc)₂ (4.2 mg, 0.02 mmol) and potassium carbonate (39 mg, 0.29 mmol) in n-butanol (5.0 mL) was stirred at 130° C. for 2 hours under N₂ atmosphere. The mixture was concentrated and the residue was purified by prep-TLC to give 8 (20 mg, 37%).

¹H NMR (400 MHz, CDCl₃): δ 8.92 (s, 1H), 7.87 (d, J=4.8 Hz, 1H), 7.73 (s, 1H), 7.52 (d, J=4.8 Hz, 1H), 4.79-4.78 (m, 1H), 3.42-3.40 (m, 1H), 3.39-3.27 (m, 2H), 3.13-3.09 (m, 1H), 2.97 (s, 3H), 2.74-2.71 (m, 1H), 2.22-2.20 (m, 3H), 1.95-1.91 (m, 1H), 1.88-1.83 (m, 1H), 1.57-1.52 (m, 1H). LCMS: m/z=286 [M+H]⁺.

Step 9: 7-(1-Bromoimidazo[1,5-a]pyrazin-3-yl)-2-methyloctahydro-1H-pyrido[1,2-c]pyrimidin-1-one (9)

To a solution of compound 8 (20 mg, 0.063 mmol, 1.0 eq) in THF (5.0 mL), was added NBS (11 mg, 0.063 mmol, 1.0 eq). The solution was stirred at rt for 30 min. The solvent was removed and the residue was purified by prep-TLC to give 9 (12 mg, 52%).

¹H NMR (400 MHz, CDCl₃): δ 8.84 (s, 1H), 7.83 (d, J=4.4 Hz, 1H), 7.56 (d, J=4.8 Hz, 1H), 4.74-4.71 (m, 1H), 3.48-3.47 (m, 1H), 3.39-3.27 (m, 2H), 3.13-3.09 (m, 1H), 2.97 (s, 3H), 2.75 (s, 1H), 2.69-2.66 (m, 1H), 2.25-2.19 (m, 3H), 1.93-1.87 (m, 3H), 1.57-1.52 (m, 1H). LCMS: m/z=363/365 [M+H]⁺.

Step 10: 7-(1-(4-(2-Fluoro-3-methoxyphenoxy)phenyl)imidazo[1,5-a]pyrazin-3-yl)-2-methyloctahydro-1H-pyrido[1,2-c]pyrimidin-1-one (10)

A mixture of compound 9 (15 mg, 0.04 mmol, 1.0 eq), (4-(2-fluoro-3-methoxyphenoxy)phenyl)boronic acid (16 mg, 0.062 mmol, 1.5 eq), PdCl₂(dppf) (3.0 mg), and potassium carbonate (11 mg, 0.0.08 mmol, 2.0 eq) in dioxane (5.0 mL) and water (0.5 mL) was stirred under reflux for 2 h. The mixture was concentrated and the residue was purified by prep-TLC to give 10 (6.0 mg, 30%).

¹H NMR (400 MHz, CDCl₃): δ 9.14 (s, 1H), 7.86-7.81 (m, 3H), 7.52-750 (m, 2H), 7.12-7.10 (m, 2H), 7.02-7.00 (m, 1H), 6.81-6.77 (m, 1H), 6.70-6.67 (m, 1H), 4.81-4.78 (m, 1H), 3.93 (s, 3H), 3.41-3.40 (m, 1H), 3.30-3.27 (m, 2H), 3.12-3.09 (m, 1H), 2.98 (s, 3H), 2.82-2.79 (m, 1H), 2.28-2.19 (m, 2H), 1.93-1.87 (m, 2H), 1.57-1.52 (m, 1H). LCMS: m/z=502 [M+H]⁺.

Examples 215 and 216 were prepared following the procedure described for Example 213 and 214:

MS (cald.) [M+H]⁺/ Entry Structure MS (found) name 215

538.21/538.2 (S)-N,N-dimethyl-2- (1-(4-(pyridin-2- ylcarbamoyl)phenyl)-8- (trifluoromethyl)imidazo [1,5-a]pyrazin-3-yl) piperidine-1-carboxamide 216

606.20/606.2 (S)-N,N-dimethyl-2-(8- (trifluoromethyl)-1-(4-((4- (trifluoromethyl)pyridin-2- yl)carbamoyl)phenyl) imidazo[1,5-a]pyrazin- 3-yl)piperidine-1- carboxamide Btk Kinase Assay and Other Kinases Assay

Btk kinase activity was determined using a homogenous time resolved fluorescence (HTRF) methodology. Measurements were performed in a reaction volume of 15 μL using 384-well assay plates. Kinase enzyme, inhibitor, ATP and 1 μM peptide substrate were incubated in a reaction buffer compose of Hepes50 mM (pH7.0), NaN3 0.02%, BSA 0.01%, Orthocanadate 0.1 mM. After one hour, the kinase reaction was quenched by the addition of Eμ-labeled antibody and XL-665 in 1×Detection buffer containing 60 mM EDTA (Cisbio), and the mixture was allowed to incubate for one hour. The HTRF signal was measured on a multimode plate reader (EnVision® Multilabel Reader, Perkin Elmer) with an excitation wavelength (2Ex) of 330 nm and detection wavelengths (λ_(Em)) of 615 and 665 nm. Activity was determined by the ratio of the fluorescence at 665 nm to that at 615 nm. For each compound, enzyme activity as measured at various concentrations of compound, Negative control reactions were performed in the absence of inhibitor in two replicates and eight no enzyme controls were used to determine baseline fluorescence levels. IC₅₀s were obtained according to the equation: Y=100/(1+10{circumflex over ( )}((Log IC50−X)*HillSlope)).

For BTK assay, [ATP]=80 μM, BTK=3.4 nM.

For LYN assay, [ATP]=20 μM, LYN=0.12 n M. For LCK assay, [ATP]=20 μM, LCK=0.2 nM. For BLK assay, [ATP]=20 μM, BLK=0.6 n M.

Example 217

The following Table shows the activity of selected compounds of this invention in the BTK inhibition assay. The compound numbers correspond to the compound numbers in previous Tables. Compounds having an activity designated as “A” provided an IC 50≤10 nM; Compounds having an activity designated as “B” provided an IC₅₀ 10-100 nM; Compounds having an activity designated as “C” provided an IC₅₀ 100-1000 nM; Compounds having an activity designated as “D” provided an IC₅₀ 1000-10000 nM; Compounds having an activity designated as “E” provided an IC₅₀≥10000 nM.

BTK Inhibition Data Compound BTK Compound BTK Compound BTK Compound BTK # Inhibition # Inhibition # Inhibition # Inhibition 1 A 2 B 3 D 4 C 5 B 6 A 7 B 8 C 9 B 10 B 11 B 12 B 13 B 14 D 15 E 16 A 17 C 18 C 19 C 20 A 21 C 22 A 23 B 24 D 25 B 26 B 27 A 28 A 29 A 30 A 31 C 32 D 33 D 34 B 35 D 36 B 37 D 38 E 39 C 40 A 41 B 42 B 43 B 44 C 45 B 46 C 47 C 48 A 49 B 50 B 51 C 52 C 53 C 54 C 55 A 56 B 57 B 58 B 59 C 60 B 61 A 62 A 63 C 64 A 65 B 66 D 67 D 68 A 69 A 70 B 71 C 72 B 73 B 74 A 75 B 76 B 77 C 78 B 79 C 80 B 81 C 82 A 83 B 84 A 85 A 86 A 87 E 88 B 89 A 90 B 91 C 92 A 93 A 94 A 95 A 96 A 97 A 98 A 99 B 100 A 101 B 102 E 103 B 104 A 105 A 106 A 107 B 108 E 109 C 110 D 111 D 112 E 113 C 114 B 115 C 116 E 117 E 118 C 119 B 120 B 121 D 122 E 123 C 124 B 125 B 126 B 127 D 128 D 129 C 130 D 131 C 132 D 133 C 134 D 135 B 136 B 137 D 138 D 139 B 140 C 141 B 142 D 143 B 144 D 145 B 146 D 147 D 148 C 149 D 150 B 151 C 152 C 153 D 154 B 155 C 156 B 157 C 158 C 159 D 160 D 161 B 162 D 163 D 164 D 165 C 166 D 167 D 168 B 169 C 170 A 171 B 172 B 173 D 174 A 175 C 176 B 177 C 178 C 179 D 180 C 181 D 182 B 183 C 184 A 185 C 186 C 187 D 188 B 189 C 190 E 191 E 192 E 193 C 194 A 195 B 196 C 197 A 198 B 199 E 200 E 201 D 202 E 203 C 204 A 205 B 206 A 207 C 208 C 209 C 210 C 211 B 212 B 213 C 214 C 215 E 216 E

Example 218

The following Table shows the activity of selected compounds of this invention in the BTK, TEC, BLK, LYN, LCK inhibition assay. The compound numbers correspond to the compound numbers in previous Tables. Compounds having an activity designated as “A” provided an IC₅₀≤10 nM; Compounds having an activity designated as “B” provided an IC₅₀ 10-100 nM; Compounds having an activity designated as “C” provided an IC₅₀ 100-1000 nM; Compounds having an activity designated as “D” provided an IC₅₀ 1000-10000 nM; Compounds having an activity designated as “E” provided an IC₅₀≥10000 nM; N/A is not available.

TABLE 2 BTK TEC LYN LCK EGFR ITK Compound IC₅₀ IC₅₀ IC₅₀ IC₅₀ IC₅₀ IC₅₀ 1 A C E E C D 5 B C E E C E 16 A C E E D D 20 A C E E D D 27 A C E E C D 30 A C E E D D 136 B C E E D D Calcium FluxAssay

Calcium flux fluorescence-based assays were performed in aFDSS7000EX (Hamamatsu Photonics) fluorometric imaging plate reader according to manufacturer instructions. Compounds to be assayed were dissolved in DMSO, diluted to appropriate concentrations in Ca²⁺ buffer ranging from 0 to 10 μM (at a dilution factor of 0.1), added 5 μl (6×) to each well (the final DMSO concentration was 0.1% in each well). Then 12.5 μL 2× dye loading solution (Fluo-4 NW Calcium Assay Kits, Invitrogen) was added per well of a 384-well plate. Afterwards, actively growing Ramos cells (ATCC) in RPM1640 medium supplemented with 10% FBS (Invitrogen) were washed and re-plated in assay buffer (from Fluo-4 NW Calcium Assay Kits, Invitrogen) to approximately 6.4×10⁶/ml (80000 cells/12.5 μL in 384-well plates). The plates were incubated at 37° C. for 30 minutes, then at room temperature for an additional 30 minutes. The plates were now ready to be used in an experiment. Immediately after the transfer and a 10-s recording of baseline fluorescence, the compound treated cells were stimulated with a goat anti-human IgM antibody (10 g/ml; Jackson Immuno Research) and read in a FDSS for 240 seconds. Difference between the signal and that at baseline, designated adjusted relative fluorescence unit, was calculated by using a custom Excel (Microsoft, Redmond, Wash.) template to determine IgM-induced calcium influx and its inhibition by compounds. The table belows show the result. Compounds having an activity designated as “A” provided an IC 50≤10 nM; Compounds having an activity designated as “B” provided an IC₅₀ 10-100 nM; Compounds having an activity designated as “C” provided an IC₅₀ 100-1000 nM;

TABLE 3 Compound Ramos Ca Flux (nM) Example 1 N/A Example 30 N/A Btk Occupancy in Cellular Assays

For PCI-33380 labeling of human B cells, 10⁶ Jeko-1 cells were pre-incubated with compound for 1.5 h before labeling. Then cells were treated with PCI-33380 at 5 μM for 1 h. Washed, lysed in Ripa buffer containing sample reducing agent, and analyzed by SDS/PAGE and fluorescent gel scanning using a Typhoon scanner 9500 (GE Healthcare) (Ex, 532 nm; Em, 555 nm). The gel was then blotted and total Btk levels detected by standard Western blot with Btk antibody (CST).

By using the fluorescently tagged derivative PCI-33380, we found that 100 nM of Compound 1 and 30, 50 nM of Compound 6, 25 nM of Compound 27, 25 nM of compound 206 were sufficient to fully occupy the active site of Btk in human mantle cell lymphoma cell lines Jeko-1 cells in culture.

Btk Occupancy In Vivo

For analysis of Btk occupancy in Babc/L mice following oral dosing of compounds after 4 hours. Isolating peripheral blood mononuclear cells (PBMCs) with mouse peripheral blood separation kit (Hao Yang Biological Manufacture CO., LTD, Tianjin) were collected from Babc/L mice (1 ml blood from two mice). Spleens were processed to splenocytes followed by 5 min incubation in red blood cell lysing buffer (from mouse peripheral blood separation kit). PBMCs or splenocytes were then PCI-33380-labeled and lysates analyzed by fluorescent gel scanning as described in cellular assays. Compound 1 and 30 were achieved full occupancy at 5 mg/kg single oral dose in all Babc/L mice. Compound 5 and 27 were achieved full occupancy at 10 mg/kg single oral dose in all Babc/L mice. 

What is claimed is:
 1. A compound of Formula (I) having the following structure:

wherein: A and G are CH, and B is N, D is CR¹; R¹ is —COOCH₃, —CH₂OH, —CH₂OCOCH₃, —CH₂CH₃, —CH₂CH₂CH₃, —CH₂CH₂CH₂CH₃, —CH(CH₃)₂, —OCH₃, —OCH₂CH₃, —OCH₂CH₂CH₃, —OCH₂CH₂CH₂CH₃, —OCH(CH₃)₂, —CH₂F, —CF₃, —OCH₂CH₂OCH₃, —OCH₂CH₂N(CH₃)₂, C₁₋₄alkoxy substituted with one to five fluorines, C₁₋₄alkoxy substituted with OH, C₁₋₄alkoxy substituted with OCH₃, NH₂ or N(CH₃)₂,

R² is

X is O, OCR^(a)R^(b), CR^(a)R^(b)O, S(O), S(O)₂, CR^(a)R^(b), NR^(c)(C═O), C═ONR^(c) or a bond; and E is an aryl substituted with one to three R⁵ substituents; R⁴ and R⁵ are each independently selected from the group consisting of hydrogen, halogen, hydroxy, cyano, OCF₃, OCF₂H, C₁₋₆ alkyl, optionally substituted with one to five fluorines, C₃₋₆ cycloalkyl, optionally substituted with one to five fluorines, C₁₋₄alkoxy, optionally substituted with one to five fluorines, C₁₋₄ alkylthio, optionally substituted with one to five fluorines, C₁₋₄ alkylsulfonyl, optionally substituted with one to five fluorines, carboxy, C₁₋₄ alkyloxycarbonyl, and C₁₋₄ alkylcarbonyl; R^(a) and R^(b) are each independently hydrogen, fluorine, or C₁₋₃ alkyl, optionally substituted with one to five fluorines; R^(c) is hydrogen or C₁₋₃ alkyl, optionally substituted with one to five fluorines; and R³ is is selected from the group consisting of:

Y is C(═O), OC(═O), NHC(═O), S═O, S(═O)₂, or NHS(═O)₂; and R⁶, R⁷, R⁸ are each independently hydrogen, halogen, CN, C₁₋₄ alkyl, C₁₋₆ alkoxyalkyl, C₁₋₈ alkylaminoalkyl, or C₁₋₄ alkylphenyl; or R⁷ and R⁸ taken together form a bond, a stereoisomer thereof, a tautomer thereof, or a pharmaceutical acceptable solvate thereof.
 2. A compound selected from the group consisting of:


3. A pharmaceutical composition comprising a therapeutically effective amount of the compound of claim 1, and a pharmaceutically acceptable excipient. 